1983 lines
82 KiB
Plaintext
1983 lines
82 KiB
Plaintext
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ACIRAN V3.4
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Linear AC Circuits Analysis
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Introduction.
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-------------
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ACIRAN is a Linear AC Circuit Analysis Program designed to ease small signal
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ac analysis of active and passive circuits. ACIRAN can handle Resistors,
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Capacitors, Inductors, Transformers(Ideal), Fets, Transistors, Operational
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Amplifiers, Transmission Lines, and Voltage Controlled Current Sources.
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Using these circuit elements almost any linear circuit can be represented and
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analysed. To save time and ease design a number of Fet,Opamp and Transistor
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model parameters have been supplied. Should a more complex model be needed
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these can be built up using passive components and Voltage Controlled Current
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sources.
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Installation.
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-------------
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Two versions of ACIRAN are supplied on a registered disk, a standard version
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and a TURBO version which runs much faster but limits the circuit size.
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Both are completely compatible, but use Turbo whenever possible as it is
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four times faster.
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ACIRAN V3.4 was created using the Turbo Pascal Compiler (V 5.5) and
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is able to support co-processors, if you machine has a floating point chip
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this is detected by ACIRAN and used for all calculations, if you do not have a
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co-processor, it is simulated by software. Obviously the program runs much
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faster with the co-processor chip fitted.
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Before using ACIRAN first make a backup copy on another disk,including all
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model and circuit files, then put the original in a safe place.
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Aciran can be run from a single floppy drive, but a hard disk is
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recommended. Copy Aciran.exe, all model files, ie those with extensions
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ending in TRN,FET, and AMP, and all circuit examples, those ending in
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CIR to your working disk. Alternatively create a subdirectory on your
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hard disk to hold these files.
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Getting Started.
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-------------------
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At the DOS prompt type ACIRAN <return> and the ACIRAN sign on screen will
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appear showing the version number and the circuit constraints.Press any
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key to continue and the copyright notice and circuit constraints will
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be removed.
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The main menu offers the following selection:
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File Edit Config Data Analyse Results Graph
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and selection is made by typing the first letter of the word or using the
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cursor keys to point to the desired function and then pressing the return key,
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or using the mouse to select the function, and clicking on the left mouse
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button.
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File
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----
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File provides the following sub-menu
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New
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Load
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Save
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Quit
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and again selection is made by typing the first letter of the word or using the
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cursor keys to point to the desired function and then pressing the return key.
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New is used to enter a new circuit description to ACIRAN and as it clears
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any previous circuit from memory you should save any data that you have
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in memory first.
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Load
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----
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Load allows you to load a previously saved circuit for analysis or
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modification. Circuits are expected to have extension .CIR (automatically
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appended by ACIRAN). You will be presented with a Lotus 123 style file
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selection box. Use the cursor keys or mouse to highlight the file you wish
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to load and then press return or click the left mouse button. Press Escape
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or the right mouse button to abandon the Load opertion. You can select other
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directories by selecting the double dots at the top of the list, and then
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move around other directories. Press F1 if you need help on using the
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file selector. If you are using the profesional or network version of
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Aciran you can change drives by selecting Alt-C.
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Save
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----
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Save allows you to save your circuit description to disk. If you are entering
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a large circuit then you should save it periodically.
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Names up to 8 characters are allowed. Longer names will be truncated to 8
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characters, do not add a file extension. Full pathnames are supported,
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and you will normally be presented with the current directory path.
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Quit
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----
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Quit will exit from ACIRAN and take you back to DOS. Any circuit description
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held in memory will be lost so make sure you have saved any data that you
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want to keep. ACIRAN will give a warning if you have not saved your circuit
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and have made changes.
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Edit
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----
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Edit allows you to make changes to the circuit description such as adding
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or deleting components and changing component values. Edit has its own
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sub-menu which will be described later.
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Config
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------
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Config allows you to select your printer type, set up certain flags and
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to request additional circuit parameters such as impedance and return loss.
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This information is stored in a config file, and along with the circuit
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details in the files.Config has it's own sub-menu which will be descibed later.
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Data
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----
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Data allows you to inspect your circuit description by listing the components,
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their values and circuit connections. A sub-menu allows you to send the
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data to the screen or to a printer.
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Analyse
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-------
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Analyse instructs ACIRAN to analyse the circuit in memory. An error message
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will be issued if there is no circuit present. Logarithmic and Linear frequency
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sweeps are allowed. ACIRAN can also carry out Monte-Carlo analysis if component
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tolerances have been entered.
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Results
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-------
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A sub-menu overs the choice to Display,Print or File. To view the results
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select Display, to obtain a hard copy of these result the Print option
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should be selected.Results can also be stored in a text file for later use,
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(eg. in reports) using the File option.
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Graph
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-----
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If your system has a Graphics card present ACIRAN can output Graphs of
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Frequency vs Amplitude,Phase,Time-delay,Impedance,Return Loss and VSWR on
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to the screen, and a hardcopy to a graphics printer.(Epson FX800, LaserJet,
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or PostScript)
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Entering New Data
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-----------------
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At the main menu press 'N' (or use the cursor keys) to select New circuit.
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The Menu window will now show NEW CIRCUIT and the Status window will ask you
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for the Name of your circuit (up to 30 characters). As DOS only supports file
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names of up to 8 characters a circuit identifier is useful to give meaningful
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names to your circuits.
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Enter a circuit name and press <return>. The Status window will now ask if you
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wish to enter component tolerances. If you answer 'Y' then ACIRAN will toggle
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on the tolerance flag and use the tolerance values entered for each component,
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if you do not enter a tolerance it will default to 0%, this is used in
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monte-carlo analysis, described later.
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Next you will see a list of component types in a pop up Menu window,use
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the normal selection methods to choose a component type. If the component
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type is Fet, Opamp or Transistor you will be asked if you wish to load model
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parameters from disk.
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If you select to do so you will be presented with another file selection
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box, to choose the component model.
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An Example
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A number of examples are included on the disk.
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They will provide the most ideal method of learning ACIRAN. Enter the first
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one from the keyboard. The circuit is shown below:
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RC Filter
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R1
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node 1 ________ node 2
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0---------| |---------------------o-------------------------0
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-------- |
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100 +/- 0.5% |
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----
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INPUT ---- OUTPUT
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o node 3
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----- 0.001uF +/- 10%
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_____
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| C1
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node 0 |
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0_______________________________________o_________________________0
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Select New Circuit.
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Enter the circuit description 'RC Filter' <cr>, and select 'Y' for tolerance
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entries.
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When the Select component menu is displayed,choose a resistor, and a form
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will appear on the screen ,you will be asked for the component identifier,
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enter 'R1' and press <return>.(Up to 5 characters can be entered for the
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component identifier).
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You will now move to the next input filed, you will then be asked for the
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value of R1. Enter 100 <return>.
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You will then be asked for the tolerance in %. Enter 0.5 <return>. (The
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leading Zero is essential).
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Next you will be asked 'From Node', Enter 1 <cr>, and then 'To node', Enter
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2 <cr>.
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The convention in ACIRAN is that the INPUT NODE is ALWAYS 1 and
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the GROUND NODE is ALWAYS 0. The OUTPUT NODE is variable(more about this
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later).
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Once you have completed the form you must enter F10 to exit and save you data.
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If you press Esc the data will be ingored. You can move around the input form
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changing the information using the edit keys, until you are happy with what
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you have entered. This free format screen input is used extensively in ACIRAN
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to give maximum flexibility. In some cases, eg frequency, the previously
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entered data is presented and can be accepted by entering <cr>.
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Enter component R2 in the same way, it is not important which way round
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the passive component is connected.
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To enter C1 select Capacitor, and for the value enter 0.001u. the 'u' or 'U'
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at the end tell ACIRAN that the value is in microfarads.
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A number of multiplier options are allowed and upper or lower case can be
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interchanged in all cases except 'M' and 'm'.
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The multipliers accepted by ACIRAN are
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'G' or 'g' Giga = x1E9
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'M' Mega = x1E6
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'K' or 'k' Kilo = x1E3
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'm' milli = x1E-3
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'U' or 'u' micro = x1E-6
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'N' or 'n' nano = x1E-9
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'P' or 'p' pico = x1E-12
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These multipliers can be entered in a number of formats, eg 1k2, 1K2,1.2K
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1200 12e2,12E2 and 1.2e3 are all acceptable and identical .
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Now that the circuit has been entered press <Esc> in response to next
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component and you will be asked for the Output node.
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If you press <cr> without entering any data ACIRAN will assign the highest
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node used to the output node. In this circuit this is not the case and you
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must enter 2 <cr>.
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It is advisable to save your work and so as soon as the main menu returns
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press 'F' for File then 'S' for Save.
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When asked for a file name enter any valid filename, remember to omit any file
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extension.
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You can check your circuit configuration by selecting Data. A short menu will
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appear offering Display and Print. Display will list to the console and
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Print to the LPT1 or PRN device. (If you are not sure about the LPT1 device
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consult your DOS handbook).
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You should not select Print unless you have a printer ready on-line.
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In this case select Display and you will see the circuit listed on the screen.
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Check that the circuit connections are correct.
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If you do not wish to enter the circuit yourself you can load it from the disk
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by selecting Load at the main menu loading 'EXAMPL1'.
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Now analyse the circuit by Selecting Analyse at the main menu.
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A frequency input form will appear, you must complete at least the
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first three entries, some have minimum default values already
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loaded.
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You can select Log or Linear sweep from the Config menu,the default is Log.
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This can be toggled by selecting Sweep when in the Config menu.
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For the moment leave it as Log.
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Now enter the start frequency. Enter 100k and press <cr>.
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Enter End frequency 100M (note capital 'M' for Megahertz).
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Finally enter the number of frequency steps, 10 <cr>.
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Leave the default number of passes as 1. Remember to press F10 once you are
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satisfied with the input data.
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If however you enter a number greater than 1 then ACIRAN will analyse your
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circuit that number of times, and on each pass it will vary the component
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values within the tolerance limits you specified for each component.
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This feature will be discussed later.
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ACIRAN will now analyse your circuit from 100 kilohertz to 100 megahertz
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in 10 Logarithmic steps. The Sweep mode selected will remain in force in
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future analysis unless you specifically change it. During Analysis the
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frequency sweep mode and range are displayed and a counter shows the percentage
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of the analysis completed.The output window will show the results of the
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frequency response of your RC Filter.
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The main menu will re-appear and if you have a printer and want a hard copy
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of the result press 'R' to select Results, and at the sub-menu select Print.
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If you have a Graphics card fitted then you can display a Graph of the
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results by pressing 'G' (Graph) from the main menu. Press the Spacebar to
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step through each graph in turn. These two features only function when ACIRAN
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has a circuit in memory and an Analysis has been performed.
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If your printer has Graphics capability you can obtain hard copies of the
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graphical results in one of two ways. When the first Graph of Frequency
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vs Amplitude appears you normally press the Spacebar to move onto the next
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Graph.
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If however you press 'P' or 'p' you will get a Printout of the screen
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dumped to your printer. Alternatively if you are familiar with DOS
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put GRAPHICS and GRAFTABL in your Autoexec.bat file to make sure that these
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files are resident before running ACIRAN.
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Then when the Graph you want to print is on the screen, simply press the
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PrtScrn key. This prints sideways and gives a much better output. (Note
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that GRAPHICS is not compatable with all modes of display,whereas the built
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in screen dump facility is).
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The results for the RC Filters are shown below.
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Transmission Results for RC Filter
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Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
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1.000E+05 -0.021 -3.594
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1.995E+05 -0.081 -7.133 -9.848E-08
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3.981E+05 -0.314 -13.951 -9.421E-08
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7.943E+05 -1.133 -25.910 -8.015E-08
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1.585E+06 -3.381 -41.920 -4.897E-08
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3.162E+06 -7.449 -54.176 -1.521E-08
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6.310E+06 -12.380 -55.459 1.380E-09
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1.259E+07 -16.738 -45.100 4.859E-09
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2.512E+07 -19.376 -29.062 3.073E-09
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5.012E+07 -20.414 -15.964 1.112E-09
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1.000E+08 -20.720 -8.214 3.125E-10
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Monte-Carlo
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Select Analyse again, but this time change the number of tolerance passes
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to 3 . It is not necessary to enter the Start and End frequencies again,or
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the number of steps, as ACIRAN will remember the previous values. You can
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however change any one of them (or all) if you wish. It is only necessary
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that you do not try to violate the input requirements (such as End frequency
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coming before Start frequency or a Log sweep on too small a frequency range).
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Keep the same frequency range and number of steps as before, and so enter <cr>
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for each entry. This time during Analysis the Status window shows the current
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Monte-Carlo pass being executed. At each pass the circuit is analysed using
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component values selected at random from within component tolerance limits.
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After analysis ACIRAN will output the results but this time the heading Upper
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Limit appears. This shows the upper limits reached during the Monte-Carlo
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passes. The Lower Limits are printed next. If you select Graph you will see not
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one but two graphs showing the spread of results obtained. This tolerance
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analysis lets you see how your circuit is likely to vary in performance
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due to component tolerances. In this example only 3 passes have been selected
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but in practice several hundred passes may be needed to give a representative
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picture.
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However this would take a lot longer and for large circuits the time can become
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excessive especially if there are a large number of frequencies.
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The largest number of passes is 32767.
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Transmission Results for RC Filter
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Upper Limit
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Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
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1.000E+05 -0.018 -3.379
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1.995E+05 -0.067 -6.484 -5.843E-08
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3.981E+05 -0.299 -13.614 -7.385E-08
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7.943E+05 -1.074 -25.274 -6.628E-08
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1.585E+06 -2.929 -39.513 -4.426E-08
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3.162E+06 -6.685 -52.542 -9.989E-09
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6.310E+06 -11.976 -55.550 1.063E-09
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1.259E+07 -16.502 -43.637 5.704E-09
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2.512E+07 -19.260 -29.356 2.645E-09
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5.012E+07 -20.320 -14.844 1.141E-09
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1.000E+08 -20.538 -7.840 4.125E-10
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Lower Limit
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Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
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1.000E+05 -0.024 -3.880
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1.995E+05 -0.087 -7.383 -8.719E-08
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3.981E+05 -0.332 -14.334 -1.266E-07
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7.943E+05 -1.317 -27.800 -1.020E-07
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1.585E+06 -3.699 -43.519 -5.053E-08
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3.162E+06 -7.164 -53.626 -1.681E-08
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6.310E+06 -12.280 -55.933 2.508E-10
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1.259E+07 -16.958 -47.009 3.180E-09
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2.512E+07 -19.423 -31.305 1.976E-09
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5.012E+07 -20.632 -16.109 8.823E-10
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1.000E+08 -20.682 -8.504 2.546E-10
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Modifications
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Having entered the circuit (either from the keyboard or from disk), it is
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necessary to be able to modify it, in order to fine tune it.
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At the Main menu select Edit, and a sub-menu appears with the
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following selection:
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Add
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Change
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Delete
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Name
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Output
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and selection is made as before.
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Add
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---
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Add allows you to extend your circuit provided there is enough room to do
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so. If you had previously saved your circuit (which you ought to do on a
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regular basis) it will allow you to carry on building your circuit from where
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you left off.
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Change
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------
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Change allows you to change a component value, and if tolerance entries
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have been selected, to change the tolerance.
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Delete
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------
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Delete allows the deletion of a component. You will be asked to confirm that
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you wish to delete the component. The components list is re-ordered to reflect
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the change.A message will confirm that the component has been deleted.
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Name
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----
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Name allows you to change the circuit identifier (or name) of the circuit.
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Output
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------
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Output allows you to change the output node. If you wish you can look at
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nodes internal to the circuit to see their response. In some cases a circuit
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may have more than one output node, for example a circuit with one input
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and two complementary outputs, perhaps with a constant phase shift between
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the two outputs.
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Esc will exit the Modify menu (as it does all sub menus) and take you back to
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the main menu.
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How to Modify a Circuit
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-----------------------
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Change
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------
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Now change the value of C1 to shift the response of the RC Filter.
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If you have exited ACIRAN restart it and load 'EXAMPL1'.
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Select Edit and then select Change. You will be presented with a Pick
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list, select C1, then <cr> or use a mouse. When asked for the value enter
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0.002u <cr>.
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The new value will be assigned to C1.Quit Edit and display the circuit
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listing, check that C1 has the new value. Select Analyse and test the
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circuit response. If you have not exited from ACIRAN you will not have
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to re-enter the Start,End and frequency Step values,nor the Output node.
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From the output results (and graphs) you can see the effect of the circuit
|
|
change. If you wish you can save this circuit, either as a new one under a
|
|
new filename,or you can overwrite the old circuit description.
|
|
|
|
Suppose for the sake of instruction it is decided that R2 should be changed
|
|
from a resistor to an inductor, this would give a notch Filter.
|
|
|
|
This can be done by first deleting R2 and then adding an inductor L1.
|
|
|
|
Do this in two stages to show the effect on the circuit listing.
|
|
|
|
|
|
Delete
|
|
------
|
|
|
|
From the main menu select Edit, and then Delete. Select R2 from the list.
|
|
|
|
It is possible to continue in Edit and do the addition, but instead Quit
|
|
and Display the circuit listing.
|
|
|
|
Notice that component R2 is no longer present.
|
|
|
|
|
|
Add
|
|
---
|
|
|
|
Re-enter Edit and this time select Add.
|
|
|
|
Press 'I' to select an Inductor.
|
|
Enter the component identity as 'L1', it's value as 0.33u (0.33 micro-henry),
|
|
Tolerance 10, and its connections 'From node' 2,'To node' 3.
|
|
|
|
Check the circuit listing.
|
|
|
|
|
|
Re-Analyse the circuit and check that it is now a notch filter. Use the
|
|
same frequency range. If you have not exited ACIRAN you need not re-enter
|
|
this data.
|
|
|
|
|
|
Add
|
|
---
|
|
|
|
Suppose the circuit is to work into a 10k load RL. Add RL to see the circuit
|
|
response. (Normally you would just change the Load in the Config menu).
|
|
|
|
Select Modify and then Add. More components can now be added to the circuit.
|
|
|
|
Select Resistor and enter 'RL' for the component identity.
|
|
|
|
Give the value 10k and a tolerance of 10%. Connect 'RL' from node 2 to node 0.
|
|
|
|
The Output node must be re-entered. If you had saved this circuit previously
|
|
and were adding more components to complete it, you may have had to update the
|
|
Output Node. Alternatively if you had deleted a component the output node
|
|
may have been removed from the circuit.
|
|
Analyse the circuit again to see the effect.
|
|
|
|
|
|
Name
|
|
----
|
|
|
|
Now that you have changed the circuit you should give it a new name.
|
|
Enter the Modify menu and select Name.
|
|
Enter 'RLC Notch Filter' <cr>.
|
|
You may wish to save your new circuit under a new filename.
|
|
|
|
Transmission Results for RLC
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.000E+05 -0.153 -7.094
|
|
1.995E+05 -0.347 -13.956 -1.899E-07
|
|
3.981E+05 -1.046 -26.445 -1.692E-07
|
|
7.943E+05 -3.118 -45.138 -1.190E-07
|
|
1.585E+06 -7.452 -64.642 -5.616E-08
|
|
3.162E+06 -14.757 -79.356 -2.012E-08
|
|
6.310E+06 -46.551 89.728 2.635E-07
|
|
1.259E+07 -14.245 78.701 -4.374E-09
|
|
2.512E+07 -7.160 63.709 -3.095E-09
|
|
5.012E+07 -2.956 44.055 -1.931E-09
|
|
1.000E+08 -0.985 25.611 -8.173E-10
|
|
|
|
|
|
|
|
How to Configure Aciran.
|
|
------------------------
|
|
|
|
Config
|
|
------
|
|
|
|
At the Main menu select 'C' for Config, and a sub-menu appears with the
|
|
following selection:
|
|
|
|
|
|
Format
|
|
Generator Zin
|
|
Load impedance Zout
|
|
Returnloss
|
|
Impedances
|
|
Sweep
|
|
Tolerance
|
|
Beep
|
|
Printer
|
|
|
|
|
|
Format
|
|
------
|
|
|
|
Format allows you to select the format used for impedance results. A
|
|
choice of Polar or Cartesian coordinates is available. Choice is made by
|
|
pressing the first letter, or postioning the menu bar and pressing <cr>.
|
|
|
|
IF you select Polar (this is the default setting) then impedance results
|
|
will be output as a Magnitude and Phase angle. On the other hand if you
|
|
select Cartesian then impedance results will be output as a Real and Imaginary
|
|
part.
|
|
|
|
|
|
Generator
|
|
---------
|
|
|
|
This option allows you to set up the source referance impedance. You may enter
|
|
values in the same format as that used for resistors (ie multipiers are
|
|
accepted).
|
|
|
|
|
|
Load
|
|
----
|
|
|
|
This option allows you to set up the load referance impedance. You may enter
|
|
values in the same format as that used for resistors (ie multipiers are
|
|
accepted).
|
|
|
|
|
|
Returnloss
|
|
----------
|
|
|
|
ReturnLoss is calculated with respect to the input and output referance
|
|
impedances. The default is 100Mohm real for both input and output. This means
|
|
that your circuit is analysed without taking into account the effect of
|
|
realistic source and load impedances.
|
|
|
|
You can change the Source and Load referance impedances to more practical
|
|
values and Return Loss and VSWR will be calcuated relative to these referances.
|
|
|
|
When Returnloss is selected, Impedance calculations are automatically enabled
|
|
as they are required to calculate Return Loss and VSWR.
|
|
|
|
Once you have changed the referance impedances they will remain in effect
|
|
until you load or enter a new circuit, or specifically alter them again.
|
|
|
|
ALL config options are saved along with the circuit data to save having to
|
|
change it every time the circuit file is loaded.
|
|
|
|
This will be illustrated later by an example.
|
|
|
|
|
|
Impedances
|
|
----------
|
|
|
|
Impedance is calculated with respect to the input and output referance
|
|
impedances.The default is 100Mohm real for both input and output. This means
|
|
that your circuit is analysed without taking into consideration the effect of
|
|
realistic Source and Load impedances.
|
|
|
|
You can change the Source and Load referance impedances to more practical
|
|
values and Input and Output impedances will be calcuated taking these
|
|
referances into account, or if you leave them unchanged you will get the open
|
|
circuit input and output impedances without loading effects. Once you have
|
|
changed the referance impedances they will remain changed until you load
|
|
or enter a new circuit, or specifically alter them.
|
|
|
|
This will be illustrated later by an example.
|
|
|
|
|
|
Sweep
|
|
-----
|
|
|
|
Sweep allows you to change the sweep mode (Logarithmic or Linear). If you
|
|
start a New circuit the Sweep mode defaults to Logarithmic. This mode
|
|
will remain in force until changed by means of the Config Sweep command.
|
|
|
|
|
|
Tolerance
|
|
---------
|
|
|
|
Tolerance simply toggles the Tolerance entries flag on and off. If, in order
|
|
to save time you selected no tolerance entries for a circuit, and at a later
|
|
date wanted to see the effect of tolerance on your circuit due to one or
|
|
more components, you can turn on tolerance by means of this switch. All the
|
|
components will originally have 0% tolerance but you can change this by
|
|
using the Change feature.
|
|
|
|
|
|
Beep
|
|
----
|
|
Beep allows you to turn off the warning beeps that are issued by ACIRAN
|
|
should you not wish to disturb others. The only exception is the case where
|
|
you are about to exit ACIRAN or load a new circuit, and have not saved your
|
|
work.
|
|
|
|
Printer
|
|
-------
|
|
|
|
Selecting this option will present a pick list of three printer types. The
|
|
default is Epson. Select Epson for dot matrix printers, LaserJet II for HP
|
|
Laser Jet Compatible printers, and Postscript for Postscript printers.
|
|
|
|
You need only do this once as Aciran stores this information along with other
|
|
config data in a file called Aciran.cfg. Each time Aciran starts it looks for
|
|
the config file, and if present loads it. On exit it writes the config info
|
|
to disk. So even if you do not have a config file to begin with, you will have
|
|
one after you run Aciran.
|
|
|
|
|
|
Further Examples
|
|
----------------
|
|
|
|
|
|
You have now covered most aspects of ACIRAN with the exception of MODELS.
|
|
How to create your own MODELS using any wordprocessor is explained in the
|
|
Appendix, for the moment simply examine how you can use the ones supplied on
|
|
the disk. To do this look at some more examples which make use of MODELS.
|
|
|
|
The next circuit (EXAMPL2 on the disk) uses a single transistor in a common
|
|
emitter amplifier, and is shown below:
|
|
|
|
Transistor Amplifier
|
|
|
|
node 0
|
|
------------o---------------------------------o--------------------
|
|
| |
|
|
| |
|
|
| |
|
|
R1 33k R4 2.7k 1%
|
|
| 1% | 5
|
|
| 4o-------C2----o--O
|
|
| BC107 C 2.2u | Output
|
|
1 2.2u |2 10% |
|
|
O-----C1----- o----------------------------B TR1 |
|
|
10% | R5 100M
|
|
Input | E | 10%
|
|
| 3o_______ |
|
|
| | | |
|
|
R2 18k R3 | |
|
|
| 1% | C3 |
|
|
| 1k | 100u | |
|
|
| 1% | 10% | |
|
|
------------o---------------------------------o-------o-----o------
|
|
node 0
|
|
|
|
|
|
|
|
|
|
Note that both power supply rails are numbered node zero. This is because
|
|
as far as AC analysis is concerned the power supply is an AC short circuit,
|
|
normally due to decoupling capacitors.
|
|
|
|
Enter the circuit as shown. When you select component type Transistor you
|
|
will be asked if you want to load model parameters, enter 'Y'.
|
|
|
|
You will be presented with a filebox similar to the type used for loading
|
|
circuit files, select a 'BC107'and press <cr> or mouse left button
|
|
.
|
|
How to add more models will be covered later.
|
|
|
|
|
|
If you enter 'N' for loading a model file ACIRAN will assume that you are
|
|
unable to supply a model file and will ask you for details of the transistor
|
|
which must be entered from the keyboard.
|
|
|
|
In either case once the Transistor parameters are loaded you will be
|
|
presented with a Transistor Form, most of the details will be filled in if
|
|
you loaded model parameters from disk (This is also true for FET and OPAMP)
|
|
model files). You must enter a circuit identifier,(this is needed to select
|
|
the component from a Pick List during subsequent edit operations), also
|
|
for the Base, Collector, and Emitter node connections, and these should
|
|
be entered with reference to the above circuit.
|
|
|
|
The default collector current is 1mA, this can be altered once you have
|
|
calculated the DC current.
|
|
|
|
Analyse the circuit from 10 hertz to 10 Megahetrz in 10 Log steps. The resistor
|
|
R5 is not needed by ACIRAN but was added so that the results of the ACIRAN
|
|
analysis could be compared with the output from a proprietary Circuit Analysis
|
|
package that runs on a Vax under VMS4.6.
|
|
|
|
The results compared almost exactly at low frequencies and only at higher
|
|
frequencies could any significant differance be spotted.
|
|
|
|
This is due to the type of transistor model used by ACIRAN which is a simple
|
|
model requiring only 3 nodes. A more precise model can be used which requires
|
|
one extra node for each transistor, and the same circuit using just such a
|
|
model is illustrated in EXAMPL3.
|
|
|
|
|
|
Transistor Amplifier Results
|
|
|
|
|
|
Transmission Results for Transistor Amplifier
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.000E+01 21.483 -75.363
|
|
3.981E+01 34.048 -100.844 -1.800E-03
|
|
1.585E+02 42.801 -137.650 -7.152E-04
|
|
6.310E+02 45.047 -167.343 -1.021E-04
|
|
2.512E+03 45.226 -176.778 -7.076E-06
|
|
1.000E+04 45.197 -179.193 -4.493E-07
|
|
3.981E+04 45.035 -179.800 -2.836E-08
|
|
1.585E+05 44.414 -179.952 -1.783E-09
|
|
6.310E+05 42.307 -179.990 -1.088E-10
|
|
2.512E+06 36.929 -179.998 -5.635E-12
|
|
1.000E+07 27.869 -180.000 -2.458E-13
|
|
|
|
Transmission Results for Transistor Hybrid Amplifier
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.000E+01 20.912 -77.921
|
|
3.981E+01 33.145 -106.462 -2.094E-03
|
|
1.585E+02 40.470 -146.085 -7.225E-04
|
|
6.310E+02 41.860 -170.581 -7.948E-05
|
|
2.512E+03 41.964 -177.795 -5.484E-06
|
|
1.000E+04 41.970 179.839 -5.459E-07
|
|
3.981E+04 41.959 177.113 -2.329E-07
|
|
1.585E+05 41.783 168.106 -2.082E-07
|
|
6.310E+05 39.662 139.859 -1.526E-07
|
|
2.512E+06 31.135 105.908 -3.236E-08
|
|
1.000E+07 19.477 91.180 -3.230E-09
|
|
|
|
|
|
|
|
A Transistor can be modeled using the Hybrid PI model as show below:
|
|
|
|
Hybrid PI Model
|
|
|
|
|
|
6 ____rbc____
|
|
2 b' | | 4
|
|
B----rbb-------o---o o----o--------o-----C
|
|
| | |____Cc___| | |
|
|
| | | |
|
|
rbe Ce rce gm
|
|
| | | |
|
|
| | | |
|
|
-----o------------------o---------
|
|
|
|
|
|
|
|
E
|
|
3
|
|
|
|
|
|
The three nodes B,C,E are the same as before,however an extra node b' is
|
|
needed to model the Transistor base spreading resistance. The parameters
|
|
shown can be calculated from manufactures test data and are dependant on
|
|
the small signal 'h' parameters, the transition frequency FT, collector
|
|
current and the transistor internode capacitances.
|
|
|
|
In EXAMPL3 the BC107 transistor has been modeled in this way. Methods of
|
|
calculating the Hybrid parameters can be found in the Appendix. The only
|
|
new component type is the Voltage controlled Current Source 'gm'.
|
|
|
|
The Source is a four terminal device which can be used to model all kinds of
|
|
active devices such as Fets and Opamps. The From node is the current source,in
|
|
this case the Collector, and the To node is the current drain. The + control
|
|
node is the drive source for the current generator, here the Base, and the
|
|
- control node is the drive sink, for a CE circuit it is the Emitter.
|
|
|
|
Analyse EXAMPL3 over the same frequency range as EXAMPL2 and examine the
|
|
differences.
|
|
|
|
|
|
The rest of this manual will describe the circuit examples supplied on the
|
|
disk. Each example was chosen to exhibit certain features of ACIRAN.
|
|
|
|
All resistors are 1% and all capacitors 10% unless stated otherwise.
|
|
|
|
|
|
EXAMPL4
|
|
-------
|
|
|
|
This is a simple transformer coupled stage connecting a 50 ohm source to a 1k
|
|
load. As ACIRAN references both Input and Output to ground it is necessary
|
|
to connect the transformer primary and secondary windings to ground for
|
|
analysis. In practice these connections could be omitted to provide DC isolation.
|
|
In transformer coupled amplifier stages where the second stage is referenced
|
|
to ground there is no problem and the transformer can be connected as normal.
|
|
|
|
As stated before ACIRAN models Ideal transformers, whereas in reality
|
|
transformers have winding resistance and inductance.These imperfections
|
|
are modeled by adding resistors and inductors to the circuit as shown below.
|
|
|
|
RP and RS are the primary and secondary DC winding resistances for the
|
|
transformer. The inductors LP and LS simulate the transformer inductances.
|
|
The primary has 1000 turns and the secondary 1080, therefore as a ratio to
|
|
one is required, enter 1.080 into the transformer form at the ratio field.
|
|
|
|
Analyse the circuit from 20 to 20k in 10 Logarithmic steps.
|
|
|
|
|
|
Transformer Coupled Stage
|
|
|
|
|
|
2 3 T1 4 5
|
|
o------RP-----o------- -------o----RS----O>---
|
|
| 19.5 | | | | 21 |
|
|
R1 50 | | | | |
|
|
| | } { | |
|
|
1O LP 1H } { LS 1H Output RL 1k
|
|
| } { | |
|
|
Input | | | | |
|
|
| | | | |
|
|
O-------------o------o--o------o----------O>---
|
|
|
|
|
|
|
|
Transformer Stage Results
|
|
|
|
Transmission Results for Transformer Coupler
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
2.000E+01 -3.663 47.985
|
|
3.991E+01 -1.347 29.088 -2.163E-03
|
|
7.962E+01 -0.501 15.580 -7.068E-04
|
|
1.589E+02 -0.260 7.955 -1.922E-04
|
|
3.170E+02 -0.197 4.006 -4.932E-05
|
|
6.325E+02 -0.181 2.010 -1.245E-05
|
|
1.262E+03 -0.177 1.008 -3.133E-06
|
|
2.518E+03 -0.176 0.505 -7.872E-07
|
|
5.024E+03 -0.176 0.253 -1.977E-07
|
|
1.002E+04 -0.176 0.127 -4.967E-08
|
|
2.000E+04 -0.176 0.064 -1.248E-08
|
|
|
|
|
|
|
|
EXAMPL5
|
|
-------
|
|
|
|
This is an Elliptic-function Bandpass Filter. The filter is to work into
|
|
a 10K Load from a 10K Source. At the main menu select Config and then at
|
|
the sub-menu select ReturnLoss.
|
|
You should then change the source and Load referance impedances,Zin and
|
|
Zout, the default is 100Mohms real. You can change these to 10K real and
|
|
0 ohms imaginary.
|
|
|
|
Quit Config and analyse the filter. The filter has a passband from
|
|
approximately 15khz to 20khz. Using a Linear sweep examine the response
|
|
from 12khz to 24khz in 10 steps. Notice that the filter response changes
|
|
sharply below 15khz and above 20khz. Now examine the response from 15khz
|
|
to 20 khz in 40 steps, in order to see how much ripple exists in the passband.
|
|
|
|
Elliptic-Function Bandpass filter
|
|
|
|
|
|
Input 48.59mH 85.65mH 30.19mH 46.39mH Output
|
|
|---L2---| |---L3---| |---L5---| |---L6---|
|
|
1 | | | | 3 | | 4 | |5 6 231.1pF
|
|
O----o----o 2o---o o-o-o o-o-o o--o--L8--o--C8--O>--
|
|
| | | | | | | | | | | 365.4mH 7 |
|
|
| |---C2---| |---C3---| | |---C5---| |---C6---| | |
|
|
--o-- 986pF 1738pF | 1820pF 2797pF | |
|
|
| | --o-- --o-- |
|
|
| | | | | | |
|
|
C1 L1 27.32mH | | | | 10k RL
|
|
| | C4 L4 18.29mH C7 L7 20.58mH |
|
|
| | 4616pF | | 4103pF| | |
|
|
--o-- | | | | |
|
|
3091pF | --o-- --o-- |
|
|
| | | |
|
|
O------o--------------------------o--------------------------o-------------O>--
|
|
0
|
|
|
|
Transmission Results for Elliptic BandPass Filter
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.200E+04 -52.119 69.862
|
|
1.320E+04 -65.659 -119.048 -8.578E-04
|
|
1.440E+04 -33.110 38.549 7.645E-04
|
|
1.560E+04 0.092 174.380 1.042E-03
|
|
1.680E+04 -0.451 42.648 -2.252E-04
|
|
1.800E+04 -0.554 -52.955 -2.137E-04
|
|
1.920E+04 0.219 -170.716 -3.333E-04
|
|
2.040E+04 -17.895 -20.975 -6.247E-04
|
|
2.160E+04 -61.207 128.039 7.892E-04
|
|
2.280E+04 -68.615 118.726 -1.755E-05
|
|
2.400E+04 -56.125 -66.878 -1.051E-05
|
|
|
|
Impedance Results for Elliptic BandPass Filter
|
|
Frequency Input Impedance Output Impedance
|
|
(Hz) (Mag) (Pha) (Mag) (Pha)
|
|
1.200E+04 3.668E+03 89.996 2.726E+04 -89.984
|
|
1.320E+04 5.510E+03 89.993 1.814E+04 -89.970
|
|
1.440E+04 1.250E+04 89.938 8.001E+03 -89.878
|
|
1.560E+04 9.765E+03 0.143 1.026E+04 -0.195
|
|
1.680E+04 1.101E+04 5.806 9.082E+03 -5.595
|
|
1.800E+04 1.116E+04 -10.058 8.988E+03 9.983
|
|
1.920E+04 9.476E+03 -0.527 1.059E+04 0.523
|
|
2.040E+04 2.620E+04 -87.452 3.805E+03 87.166
|
|
2.160E+04 7.838E+03 -89.988 1.275E+04 89.887
|
|
2.280E+04 5.410E+03 -89.994 1.847E+04 89.914
|
|
2.400E+04 4.265E+03 -89.995 2.344E+04 89.925
|
|
|
|
Return Loss Results for Elliptic BandPass Filter
|
|
Frequency(Hz) Input RL(dB) Output RL(dB) Input VSWR Output VSWR
|
|
1.200E+04 0.00 0.00 46889.2749 10870.8338
|
|
1.320E+04 0.00 0.00 20746.3939 4554.9720
|
|
1.440E+04 0.01 0.02 1882.7613 965.9286
|
|
1.560E+04 38.44 37.67 1.0242 1.0265
|
|
1.680E+04 23.11 23.28 1.1503 1.1472
|
|
1.800E+04 19.69 19.80 1.2312 1.2280
|
|
1.920E+04 31.28 30.75 1.0561 1.0597
|
|
2.040E+04 0.26 0.29 67.4989 60.8337
|
|
2.160E+04 0.00 0.02 10099.9979 1046.8380
|
|
2.280E+04 0.00 0.01 21564.9053 1597.0647
|
|
2.400E+04 0.00 0.01 34982.8926 2127.1413
|
|
|
|
|
|
|
|
EXAMPL6
|
|
-------
|
|
|
|
This is a VHF/Video amplifier using an FET.The circuit is show below:
|
|
|
|
Again note that both power rails are at node 0.
|
|
|
|
Analyse the circuit from 1M to 200M on a Log sweep.
|
|
|
|
|
|
Fet Amplifier
|
|
|
|
node 0
|
|
-----------------------------------o--------------------------------
|
|
|
|
|
|
|
|
|
|
|
L1 0.78uH
|
|
|
|
|
o 5
|
|
|
|
|
R2 560
|
|
| Output
|
|
4 o---------------O
|
|
Input S
|
|
50
|
|
O-------R1-----o----------G TR1
|
|
1 2
|
|
D
|
|
3o
|
|
|
|
|
R3 47
|
|
|
|
|
-----------------------------------o--------------------------------
|
|
node 0
|
|
|
|
Tr1 = 2N4393
|
|
|
|
|
|
Fet Amplifier Results
|
|
|
|
Transmission Results for Fet Amplifier
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.000E+06 13.851 179.567
|
|
1.699E+06 13.852 179.265 -1.202E-09
|
|
2.885E+06 13.855 178.751 -1.203E-09
|
|
4.901E+06 13.862 177.876 -1.207E-09
|
|
8.326E+06 13.881 176.378 -1.218E-09
|
|
1.414E+07 13.937 173.781 -1.249E-09
|
|
2.402E+07 14.090 169.114 -1.336E-09
|
|
4.081E+07 14.467 160.011 -1.569E-09
|
|
6.931E+07 15.037 140.042 -2.068E-09
|
|
1.177E+08 13.999 100.833 -2.209E-09
|
|
2.000E+08 9.394 60.060 -1.128E-09
|
|
|
|
|
|
|
|
EXAMPL7
|
|
-------
|
|
|
|
This example is of a Twin-T notch filter and illustrates the use of an Opamp.
|
|
The circuit is shown below:
|
|
|
|
|
|
Twin-T Filter
|
|
|
|
_________
|
|
| |
|
|
| |
|
|
0.01uF 2 0.01uF | |\ | Output
|
|
----C1----o---------C3----- --|-\ |6
|
|
| | | | \____o________O
|
|
| | | | / |
|
|
O--------o1 | 4o------|+/ |
|
|
| | | |/ |
|
|
Input | | 3 | |
|
|
----R1----+------o--R3----- A1 |
|
|
15.9k | | 15.9k |
|
|
| | R4 24.9
|
|
7870 R2 C2 0.02uF |
|
|
| | |
|
|
| 5 | |
|
|
---o--- |
|
|
| |
|
|
| |
|
|
-----------------------------o
|
|
|
|
|
|
|
|
R5 976
|
|
|
|
|
|
|
|
O--------------------------------------------------o--------O
|
|
|
|
|
|
A1 = LM124
|
|
|
|
Analyse the circuit from 10 hertz to 2k hertz in 10 Linear steps.
|
|
|
|
Note that the notch frequency occurs at about 1khz.
|
|
|
|
Twin-T Filter Results
|
|
|
|
Transmission Results for Twin-T Network
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.000E+01 0.000 -0.057
|
|
2.090E+02 0.001 -1.228 -1.678E-05
|
|
4.080E+02 -0.004 -2.712 -2.261E-05
|
|
6.070E+02 -0.029 -5.244 -4.144E-05
|
|
8.060E+02 -0.192 -12.215 -1.283E-04
|
|
1.005E+03 -20.430 78.647 2.896E-03
|
|
1.204E+03 -0.245 13.854 -3.109E-04
|
|
1.403E+03 -0.056 7.492 -6.091E-05
|
|
1.602E+03 -0.015 5.230 -2.560E-05
|
|
1.801E+03 0.003 4.052 -1.425E-05
|
|
2.000E+03 0.013 3.319 -9.179E-06
|
|
|
|
|
|
|
|
|
|
EXAMPL8
|
|
-------
|
|
|
|
This is a Single Bandpass Filter section. It has a response curve which
|
|
is the inverse of exampl7. It is designed to have a centre frequency of
|
|
3.6khz and a 3dB bandwidth of 60Hz. Analyse the circuit on a Linear sweep
|
|
from 3.0khz to 4.5khz in 10 steps.
|
|
|
|
Note that R6 is variable in order that the circuit response can be finely
|
|
adjusted.
|
|
|
|
Experiment by changing the value of R6.
|
|
|
|
|
|
Single Bandpass Filter
|
|
|
|
|
|
12.1k
|
|
_____R3________________________________
|
|
| 0.01uF |
|
|
| 10k |-------------C2---o
|
|
o-----R2---- | 88.7k |
|
|
1 | |\ | | |-----R7--o
|
|
O---R1---o--|-\ | 44.2k | 0.01uF | |\ |
|
|
20k 2 | \____o___R4___o___C1___o__|-\ |
|
|
| / 3 4| 6 | \___o_____O
|
|
--|+/ A1 | | / 7
|
|
| |/ R5 --|+/ A2
|
|
| | 174 | |/
|
|
| | |
|
|
Input | 5o---- | Output
|
|
| | | |
|
|
| | | |
|
|
| R6<-| |
|
|
| |100+/-50%|
|
|
O---------o------------------o---------o--------------O
|
|
0
|
|
A1,A2 = LM124
|
|
|
|
Single BandpassFilter Results
|
|
|
|
Transmission Results for Single BandPass Filter Section
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
3.000E+03 -17.123 97.547
|
|
3.150E+03 -14.460 100.975 7.238E-05
|
|
3.300E+03 -10.948 107.639 1.467E-04
|
|
3.450E+03 -5.935 124.839 4.052E-04
|
|
3.600E+03 -1.541 -178.534 1.319E-03
|
|
3.750E+03 -6.222 -127.853 6.657E-04
|
|
3.900E+03 -10.642 -112.776 2.065E-04
|
|
4.050E+03 -13.642 -106.677 9.252E-05
|
|
4.200E+03 -15.841 -103.460 5.149E-05
|
|
4.350E+03 -17.558 -101.489 3.255E-05
|
|
4.500E+03 -18.958 -100.164 2.234E-05
|
|
|
|
|
|
|
|
|
|
EXAMPL9
|
|
-------
|
|
|
|
This circuit is an active delay line with a gain of 20dB and a 100uS constant
|
|
within 3% to 3khz. Up till now the circuit Amplitude has been of paramount
|
|
importance, but this is not always the case. The Time or Group delay has
|
|
an important part to play especially in telecommunication circuits where
|
|
poor Group delay response can introduce distortion.
|
|
|
|
It is also possible to look at the open circuit input and output impedance.
|
|
In this example select Config and then Format. Select 'C' for Cartesian
|
|
format. Do not change the referance impedance from the default of 100Mohms.
|
|
|
|
In this example the circuit provides not only gain but almost constant
|
|
Time-delay for frequencies up to 3khz.
|
|
|
|
|
|
Analyse the circuit on a Linear sweep from 100hz to 3khz.
|
|
|
|
100uS delay Line
|
|
|
|
|
|
_____C2___________
|
|
| 0.01uF |
|
|
| 2740 |
|
|
| ___R2____o 100k
|
|
| | | ______R5___ 10k
|
|
1430 |0.01uF | |\ | | | ___R8____
|
|
--R1--o--C1---o--|-\ |4750 |5 |\ | | |
|
|
| 2 3 | \___o__R4__o__|-\ 6| 10k | |\ |
|
|
1 | | / 4 | | \____o___R6__o__|-\ |
|
|
O----o --|+/ ----- | / | 7 | \__o____O
|
|
| | |/ A1 | --|+/ A2 | 8 | / 9
|
|
| | | | |/ ---C3---o--|+/
|
|
|----R3---------+-----------| | 0.01uF | |/ A3
|
|
Input 10k | | | Output
|
|
| | R7
|
|
| | | 2150
|
|
| | |
|
|
O--------------------o----------------o-----------------o-------------O
|
|
0
|
|
|
|
A1,A2,A3 = TL084
|
|
|
|
Delay Line Results
|
|
|
|
Transmission Results for 100uS Delay Line
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.000E+02 20.006 -3.625
|
|
3.900E+02 20.015 -14.136 -1.007E-04
|
|
6.800E+02 20.026 -24.648 -1.007E-04
|
|
9.700E+02 20.037 -35.160 -1.007E-04
|
|
1.260E+03 20.049 -45.672 -1.007E-04
|
|
1.550E+03 20.061 -56.183 -1.007E-04
|
|
1.840E+03 20.075 -66.693 -1.007E-04
|
|
2.130E+03 20.090 -77.200 -1.006E-04
|
|
2.420E+03 20.105 -87.703 -1.006E-04
|
|
2.710E+03 20.121 -98.199 -1.005E-04
|
|
3.000E+03 20.138 -108.683 -1.004E-04
|
|
|
|
Impedance Results for 100uS Delay Line
|
|
Frequency Input Impedance Output Impedance
|
|
(Hz) (Real) (Imag) (Real) (Imag)
|
|
1.000E+02 9.831E+03 -1.234E+03 4.001E-03 -9.949E-08
|
|
3.900E+02 7.974E+03 -3.836E+03 9.803E-03 -7.576E-07
|
|
6.800E+02 5.727E+03 -4.633E+03 1.561E-02 -1.472E-06
|
|
9.700E+02 4.093E+03 -4.475E+03 2.141E-02 -2.001E-06
|
|
1.260E+03 3.047E+03 -4.035E+03 2.721E-02 -2.397E-06
|
|
1.550E+03 2.382E+03 -3.572E+03 3.302E-02 -2.744E-06
|
|
1.840E+03 1.948E+03 -3.157E+03 3.882E-02 -3.099E-06
|
|
2.130E+03 1.655E+03 -2.801E+03 4.463E-02 -3.496E-06
|
|
2.420E+03 1.452E+03 -2.501E+03 5.043E-02 -3.956E-06
|
|
2.710E+03 1.306E+03 -2.246E+03 5.624E-02 -4.490E-06
|
|
3.000E+03 1.199E+03 -2.029E+03 6.205E-02 -5.103E-06
|
|
|
|
|
|
EXAMPL10
|
|
--------
|
|
|
|
This is quite a large circuit and demonstrates how ACIRAN can handle even
|
|
the most complex analysis.
|
|
|
|
LowPass Filter
|
|
|
|
|
|
|
|
|
|
1 2 7500 3
|
|
O------C1----o-----R1-------o-------------------------->
|
|
0.1uF |
|
|
R2 1k
|
|
| |\
|
|
4o------|+\ A1
|
|
| | \_______.
|
|
0.1uF C2 | / |
|
|
| --|-/ |
|
|
.--------------------o5 | |/ |
|
|
| | | |
|
|
| 6190 R3 | |
|
|
| 6| | | Stage1
|
|
Input | ----o----- |
|
|
| /| | | |
|
|
| A2 /-|----| C3 0.1uF |
|
|
|_______ / | | |
|
|
\ | 7o------------------
|
|
\+|----. R4 7320
|
|
\| | |
|
|
| 8o------.
|
|
| | |
|
|
| R5 <---|
|
|
| | 500 +/- 50%
|
|
----o9
|
|
|
|
|
R6 6190
|
|
|
|
|
O----------------------------o-------------------------->
|
|
0
|
|
|
|
10
|
|
>-------------------R7-------o-------------------------->
|
|
9310 |
|
|
R8 6890
|
|
| |\
|
|
11o------|+\ A3
|
|
| | \_______.
|
|
0.1uF C4 | / |
|
|
| --|-/ |
|
|
.--------------------o12 | |/ |
|
|
| | | |
|
|
| 6190 R9 | | Stage2
|
|
| |13 | |
|
|
| ----o----- |
|
|
| /| | | |
|
|
| A4 /-|----| C5 0.1uF |
|
|
|_______ / | | |
|
|
\ | 14o------------------
|
|
\+|----. R10
|
|
\| | |
|
|
| 15o------.
|
|
| | |
|
|
| R11<---|
|
|
| | 500 +/- 50%
|
|
----o16
|
|
|
|
|
R12 6190
|
|
|
|
|
>----------------------------o-------------------------->
|
|
0
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
17
|
|
>------------------R13-------o-------------------------->
|
|
5110 |
|
|
R14 14.7k
|
|
| |\
|
|
18o------|+\ A5
|
|
| | \_______.
|
|
0.1uF C6 | / |
|
|
| --|-/ |
|
|
.--------------------o19 | |/ |
|
|
| | | |
|
|
| 6190 R15 | |
|
|
| |20 | |
|
|
| ----o----- |
|
|
| A6 /| | | |
|
|
| /-|----| C7 0.1uF | Stage3
|
|
|_______ / | | |
|
|
\ | 21o------------------
|
|
\+|----. R16 2150
|
|
\| | |
|
|
| 22o------.
|
|
| | |
|
|
| R17<---|
|
|
| | 500 +/- 50%
|
|
----o23
|
|
|
|
|
R18 6190
|
|
|
|
|
>----------------------------o---------------------------->
|
|
0
|
|
|
|
24
|
|
>------------------R19-------o---------------------------->
|
|
4120 |
|
|
R20 11.5k
|
|
| |\
|
|
25o------|+\ A7
|
|
| | \_______.
|
|
0.1uF C8 | / |
|
|
| --|-/ |
|
|
.--------------------o26 | |/ |
|
|
| | | |
|
|
| 6190 R21 | |
|
|
| |27 | |
|
|
| ----o----- | Stage4
|
|
| /| | | |
|
|
| A8 /-|----| C9 0.1uF |
|
|
|_______ / | | |
|
|
\ | 28o------------------
|
|
\+|----. R22 2670
|
|
\| | |
|
|
| 29o------.
|
|
| | |
|
|
| R23<---|
|
|
| | 500 +/- 50%
|
|
----o30
|
|
|
|
|
R24 6190
|
|
|
|
|
>-----------------------------o----------------------------->
|
|
0
|
|
|
|
|
|
|
|
31 38
|
|
>-------------------R25-------o--------------R31------o----O >--|
|
|
6650 | 5360 | |
|
|
R26 4020 | |
|
|
| |\ | |
|
|
32o------|+\ A9 | |
|
|
| | \_______. | |
|
|
0.1uF C10 | / | | |
|
|
| --|-/ | | |
|
|
.--------------------o33 | |/ | | |
|
|
| | | | | |
|
|
| 6190 R27 | | | Output|
|
|
| |34 | Stage5 | | |
|
|
| ----o----- | | |
|
|
| A10 /| | | | C12 0.1uF RL 1M
|
|
| /-|----| C11 0.1uF | | |
|
|
|_______ / | | | | |
|
|
\ | 35o------------------ | |
|
|
\+|----. R28 4990 | |
|
|
\| | | | |
|
|
| 36o------. | |
|
|
| | | | |
|
|
| R29<---| | |
|
|
| | 500 +/- 50% | |
|
|
----o37 | |
|
|
| | |
|
|
R30 6190 | |
|
|
| | |
|
|
>-----------------------------o-----------------------o----O >--|
|
|
0
|
|
|
|
A1-A10 = LM124
|
|
|
|
|
|
Low Pass Filter Results
|
|
|
|
|
|
Transmission Results for Low Pass Filter
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.000E+02 -6.035 -113.820
|
|
1.200E+02 -6.021 -141.176 -3.883E-03
|
|
1.400E+02 -6.126 -170.857 -4.201E-03
|
|
1.600E+02 -6.217 156.691 -4.632E-03
|
|
1.800E+02 -6.101 118.464 -5.601E-03
|
|
2.000E+02 -6.002 68.703 -7.408E-03
|
|
2.200E+02 -6.061 0.850 -1.030E-02
|
|
2.400E+02 -6.428 -127.396 -2.146E-02
|
|
2.600E+02 -53.155 88.245 1.657E-02
|
|
2.800E+02 -65.822 -144.033 -5.771E-03
|
|
3.000E+02 -66.648 15.946 -3.317E-03
|
|
|
|
|
|
|
|
|
|
The circuit is an Elliptic-Function Low-Pass Filter using a GIC (Generalized
|
|
Impedance Converter). Five stages of GIC are employed. The filter is designed
|
|
to have low insertion loss and ripple in the pass band up to 260Hz, and
|
|
to have a minimum attenuation outside the passband of 60dB at 270Hz.
|
|
|
|
In practice variable resistors are needed to adjust the GIC to obtain the
|
|
desired response.
|
|
|
|
Analyse the circuit from 100 to 300Hz in 10 Linear steps. This circuit will
|
|
take several minutes to Analyse.
|
|
|
|
|
|
Exampl11
|
|
--------
|
|
|
|
This example uses a Transmission line as a quarter wavelength transformer to
|
|
match an impedance of 95 ohms real to a load of 50 ohms real. The frequency of
|
|
interest is 150Mhz (2m wavelength) which gives a line length of 50cm (2m/4).
|
|
|
|
The impedace of the line to give the required match is equal to the square root
|
|
of the source impedance multiplied by the load impedance ie.
|
|
|
|
sqrt(95 * 50) = 69ohms
|
|
|
|
|
|
Transmission Line Transformer
|
|
|
|
ZL1
|
|
1 __________________________ 2
|
|
input \ _______| |____/
|
|
/ |__________________________| \ output
|
|
95 ohms Zo=69 L=50 Er=1 50 ohms
|
|
|
|
0_________________________________________0
|
|
|
|
|
|
Where Zo = characteristic impedance
|
|
L = length in cm
|
|
Er = relative permeability
|
|
|
|
|
|
The configure menu is entered and the load impedance set to 50 + j 0.00 and
|
|
the generator impedance to 95 + j 0.00. Select Return loss and Linear Sweep.
|
|
Analyse the circuit from 148Mhz to 152Mhz in 4 steps, the results are:-
|
|
|
|
Transmission Results for Transmission Line Transformer
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.480E+08 -2.797 -89.130
|
|
1.490E+08 -2.797 -89.565 -1.208E-09
|
|
1.500E+08 -2.798 -90.000 -1.208E-09
|
|
1.510E+08 -2.797 -90.435 -1.208E-09
|
|
1.520E+08 -2.797 -90.870 -1.208E-09
|
|
|
|
|
|
Impedance Results for Transmission Line Transformer
|
|
Frequency Input Impedance Output Impedance
|
|
(Hz) (Mag) (Pha) (Mag) (Pha)
|
|
1.480E+08 9.519E+01 0.786 5.013E+01 -0.780
|
|
1.490E+08 9.521E+01 0.393 5.012E+01 -0.390
|
|
1.500E+08 9.522E+01 -0.000 5.012E+01 -0.000
|
|
1.510E+08 9.521E+01 -0.393 5.012E+01 0.390
|
|
1.520E+08 9.519E+01 -0.786 5.013E+01 0.780
|
|
|
|
|
|
Return Loss Results for Transmission Line Transformer
|
|
Frequency(Hz) Input RL(dB) Output RL(dB) Input VSWR Output VSWR
|
|
1.480E+08 43.18 43.18 1.0140 1.0140
|
|
1.490E+08 48.85 48.85 1.0072 1.0072
|
|
1.500E+08 58.74 58.73 1.0023 1.0023
|
|
1.510E+08 48.85 48.85 1.0072 1.0072
|
|
1.520E+08 43.18 43.18 1.0140 1.0140
|
|
|
|
|
|
|
|
Exampl12
|
|
--------
|
|
|
|
This example makes use of transmission lines to match a source impedance to
|
|
a complex load by means of a Stub Tuner. The theory of Stub Tuner matching is
|
|
beyond the scope of this manual and the reader should refer to relevant text
|
|
books.
|
|
|
|
Stub Tuner
|
|
|
|
|
|
ZL1 ZL2
|
|
1 _______________________ 2 __________________ 3
|
|
input \ _______| |_o_| |___/
|
|
/ |_______________________| | |__________________| \ output
|
|
50ohms Zo=50 L=75 Er=1 | Z0=50 L=39.8 Er=1 100 + j 50.00
|
|
|
|
|
0__________________________________|________________________0
|
|
|
|
|
____________________________|
|
|
|
|
|
| STUB
|
|
| __________________________ 4
|
|
|____| |____
|
|
|__________________________| |
|
|
Zo=50 L=25 Er=1 /
|
|
\ Short = 1e-3 ohms
|
|
/
|
|
|
|
|
0
|
|
|
|
Where Zo = characteristic impedance
|
|
L = length in cm
|
|
Er = relative permeability
|
|
|
|
|
|
A Stub can be open or short circuit, it is better to use a short otherwise
|
|
it tends to radiate. The circuit was analysed over the same frequency range
|
|
as before. The source generator was set to 50 + j 0.00 ohms and the load set
|
|
to 100 + j 50.00, ie complex.
|
|
|
|
Transmission Results for Single Stub Match
|
|
Frequency(Hz) Magnitude(db) Phase(Deg) Time Delay(Sec)
|
|
1.480E+08 3.855 -87.104
|
|
1.490E+08 3.922 -89.076 -5.478E-09
|
|
1.500E+08 3.981 -91.066 -5.528E-09
|
|
1.510E+08 4.031 -93.071 -5.568E-09
|
|
1.520E+08 4.072 -95.085 -5.596E-09
|
|
|
|
|
|
Impedance Results for Single Stub Match
|
|
Frequency Input Impedance Output Impedance
|
|
(Hz) (Mag) (Pha) (Mag) (Pha)
|
|
1.480E+08 5.141E+01 -2.252 1.160E+02 -25.276
|
|
1.490E+08 5.065E+01 -1.059 1.138E+02 -25.999
|
|
1.500E+08 4.998E+01 0.168 1.116E+02 -26.683
|
|
1.510E+08 4.939E+01 1.424 1.095E+02 -27.328
|
|
1.520E+08 4.889E+01 2.704 1.074E+02 -27.936
|
|
|
|
|
|
Return Loss Results for Single Stub Match
|
|
Frequency(Hz) Input RL(dB) Output RL(dB) Input VSWR Output VSWR
|
|
1.480E+08 32.37 6.26 1.0493 2.8937
|
|
1.490E+08 38.95 6.13 1.0228 2.9519
|
|
1.500E+08 56.59 6.00 1.0030 3.0103
|
|
1.510E+08 37.17 5.88 1.0281 3.0687
|
|
1.520E+08 31.65 5.76 1.0537 3.1271
|
|
|
|
Where Zo = characteristic impedance
|
|
L = length in cm
|
|
Er = relative permeability
|
|
|
|
|
|
At first appearance the passive line seems to have a gain, this is due to
|
|
the impedance transformation, and although a voltage gain is produced the
|
|
current gain is less than unity and so is the power gain.
|
|
|
|
|
|
|
|
Advanced Options
|
|
|
|
Aciran uses a unity voltage generator as it's source. This is the same as
|
|
having an AC voltage generator of 1VAC connected between nodes 1 and 0.
|
|
|
|
The result is that the gain/loss of the circuit being analysed is the output
|
|
value presented, and in most cases there is no reason to change this. In the
|
|
next section you will read about SPAC, the PSpice to Aciran file conversion
|
|
utility which is supplied to registered users. Aciran is able to accept
|
|
independant Voltage and Current Sources for PSpice compatibility, but these
|
|
are normally relaced with AC short circuits, in order to preserve the circuit
|
|
topology. If the source is connected across the input terminals then it is
|
|
completely ignored.
|
|
|
|
The exception is where the source is an AC Voltage source,in this case its
|
|
value is used as an input reference in the same way that PSpice uses such
|
|
inputs. This means that you can set the input voltage to Aciran by connecting
|
|
an AC Voltage source to the input terminals.
|
|
|
|
|
|
|
|
SPAC Conversion Utility
|
|
|
|
|
|
Up until now input to ACIRAN has been via the keyboard. SPAC is a
|
|
conversion utility which allows you to input PSpice circuit files to
|
|
ACIRAN. PSpice files are stored as ascii text and spac will read these
|
|
files and attempt tp convert them into an Aciran file.
|
|
|
|
At the prompt type SPAC <cr>.
|
|
|
|
You will see a version number and copyright notice and be asked to enter
|
|
a PSpice filename. Full paths are allowed, but make sure that if the PSpice
|
|
circuit has any include files, that these are located in the current path or
|
|
directory.
|
|
|
|
As it progresses SPAC will report on it's progress, the info is also written
|
|
to an ascii text file called SPAC.LOG which you can inspect later if there
|
|
are any problems. After it has completed you will be asked for the name of
|
|
an Aciran file name in which to store the data.
|
|
|
|
During the conversion SPAC may come across component types it cannot handle,
|
|
you will be notified of these, and of any substitutions that take place.
|
|
The three files standard.amp, standard.fet and standard.trn must be in the
|
|
same directory as SPAC, as these are used to supply model info if SPAC is
|
|
unable to find PSpice models that it knows.
|
|
|
|
PSpice node numbering is somewhat erratic, and so SPAC renumbers the nodes
|
|
starting at 1. To help you see what has happened a node table is produced
|
|
showing the old and new node numbers. This is needed if SPAC is unsure of
|
|
the output node, or if any components cannot be handled and you have to enter
|
|
then manually from Aciran.
|
|
|
|
If SPAC has had to assume the output node, you should find out what it is in
|
|
the PSpice circuit, look up the node table to find out what SPAC has changed
|
|
it to, and then use the Edit command in Aciran to change the output node to
|
|
the correct number.
|
|
|
|
|
|
|
|
|
|
ACTRAN Conversion Utility
|
|
|
|
|
|
Up until now input to ACIRAN has been via the keyboard. ACTRAN is a
|
|
conversion utility which allows you to input ORCAD netlist files to
|
|
ACIRAN. ORCAD is a schematic design package which is capable of outputing
|
|
circuit information in a number of CAD formats. This netlist file can then
|
|
be used by other CAD systems such as a PCB layout package.
|
|
|
|
All the information needed by ACIRAN can be obtained from an ORCAD netlist
|
|
in the SPICE format. If you have used ORCAD to produce your circuit
|
|
diagrams it makes sense to use Actran to convert the netlist file into an
|
|
ACIRAN circuit file, rather than enter the whole circuit again by hand.
|
|
|
|
The ORCAD system comes complete with a number of component libraries
|
|
however these may not all be in the correct format for SPICE netlist files
|
|
and normally these would need modification. To simplify matters an ACIRAN
|
|
library called ACIRAN.LIB is supplied which contains most of the elements
|
|
used by ACIRAN in the spice format.For more detailed information on ORCAD
|
|
libraries you should consult your ORCAD handbook.
|
|
|
|
|
|
How to use ACTRAN
|
|
|
|
Start by adding ACIRAN.LIB to the begining of the list of Library files
|
|
used by Draft. This will ensure that draft will look in ACIRAN.LIB first
|
|
for any components that it uses.Create your circuit in the normal way.
|
|
|
|
ACIRAN circuits have one input and one output node and it is necessary to
|
|
tell it what these nodes are in the ORCAD circuit. This is done by having
|
|
one input module port called 'input' and one output module port called
|
|
'output'. The node numbers corresponding to these modules are placed in a
|
|
MAP file by Netlist where they are read by ACTRAN.
|
|
|
|
Let us assume that you have produced a circuit using ORCAD. Most of the
|
|
circuit examples supplied with ACIRAN are given in their ORCAD form as well
|
|
as ACIRAN circuit files. Once you have annotated and carried out an
|
|
electrical rules check on you circuit without any errors being found use
|
|
Netlist to generate a netlist file in the SPICE format thus:
|
|
|
|
Netlist <CircuitFileName> <NetlistFileName> /S Spice <cr>
|
|
|
|
The Netlist utility supplied by ORCAD will produce two files ,a net file
|
|
and a map file, both of which are used by ACTRAN.
|
|
|
|
Having successfully produced a Net and Map file in the SPICE format we are
|
|
now ready to run ACTRAN. At the DOS prompt type ACTRAN <cr>. The ACTRAN
|
|
screen will appear and you will be prompted for the netlist filename. Full
|
|
path names are supported. If ACTRAN is successfull in finding the files it
|
|
will report on its progress on the output window while it processes the
|
|
netlist information.
|
|
|
|
Should ACTRAN come across any unknown component types these will be ignored
|
|
and a warning will be issued. ACTRAN also produces a LOG file which
|
|
contains a record of all screen output. Once ACTRAN has completed it's work
|
|
you should examine ACTRAN.LOG to check for any errors, this is a simple
|
|
text file which can be viewed by using the TYPE command.
|
|
|
|
There is the possibility that you will be using transistor, FET and OPAMPs
|
|
that are not listed in the models directory.ORCAD only has the designator
|
|
Q? for both Transistors and FET's and therefore ACTRAN is unable to
|
|
distinguish between them. ACTRAN assumes the component is a FET and looks
|
|
in the models directory for a FET of the given type. If it is not
|
|
sucessfull it then tries to find a transistor of the given type. If the
|
|
component type is still not found ACTRAN leaves it as a transistor and
|
|
gives it the name STANDARD. The Model file STANDARD contains information on a
|
|
general purpose NPN transistor. Actran tells the user that this
|
|
substitution has taken place. A similar event takes place when ACTRAN is
|
|
unable to find model files for Opamps. All Opamps have the designator U?,
|
|
and ACTRAN only expects to find Opamps ic's and therefore the presence of
|
|
other Integrated Circuits will only lead to confusion.
|
|
|
|
After completing the transfer ACTRAN will ask for a circuit Description of
|
|
up to 30 characters. This is simply the Name that you normally add to a
|
|
ACIRAN circuit file to identify it. Next you will be asked for a file name
|
|
and you should enter any valid ACIRAN circuit file name. ACTRAN will now
|
|
store the circuit file in your circuits directory.
|
|
|
|
|
|
It is important how the values of some components are entered in the ORCAD
|
|
sheet so that ACTRAN can read them correctly. The majority of components are
|
|
straight forward however Transformers and Transmission Lines are more
|
|
particular. You should study the example files provided in the ORCAD directory.
|
|
Note that Transformers require the turns ratio to be supplied as
|
|
|
|
<primary turns> <space> : <space> <secondary turns>
|
|
^
|
|
colon
|
|
|
|
and that Transmission lines require their parameters to be stated as
|
|
|
|
Zo=<char impedance> <space> L=<length in cm> <space> Er=<permeability>
|
|
|
|
The colon and equals signs are important, as well as the order of parameters.
|
|
|
|
|
|
|
|
Appendix A - Model Files.
|
|
|
|
|
|
ACIRAN uses model files to hold descriptions of Transistors Fets and Opamps.
|
|
You can create your own model files and add them to the Models directory using
|
|
any text editor or wordprocessor such as WordStar(Do not use any control codes).
|
|
|
|
The model for the BC107 Transistor used in EXAMPL2 is shown below:
|
|
|
|
|
|
BC107
|
|
2.7k
|
|
18U
|
|
192
|
|
35%
|
|
300M
|
|
|
|
The file consists of lines of text. Each line contains ONE and only one
|
|
parameter and all parameters MUST be supplied. The information can be obtained
|
|
from manufacturers data sheets.
|
|
|
|
The first line contains the component name 'BC107' ( max of 8 characters).
|
|
Next comes the value of hie, followed by hoe and hfe. The tolerance value
|
|
refers to hfe.
|
|
Transistor hfe values can vary enormously even for the same type of transistor.
|
|
The 'h' parameters of a transistor vary with temperature and collector current.
|
|
|
|
Last comes the value of FT. Note the use of multipliers, hie could just have
|
|
easily been written as 27e2, 27E2 or 2700. Transistor model files MUST be
|
|
given the extension .TRN.
|
|
|
|
|
|
The Fet model file for the 2N4393 Fet used in EXAMPL6 is shown below:
|
|
|
|
|
|
2N4393
|
|
15m
|
|
45%
|
|
11.5p
|
|
2p
|
|
|
|
|
|
Again the same rules apply as for the transistor file. First comes the name,
|
|
followed by the transconductance gm, the tolerance for gm, the Fet capacitances
|
|
Cgs and Cgd. Fet model files MUST have the file extension .FET.
|
|
|
|
|
|
|
|
|
|
The last model type supported by ACIRAN is the Opamp model. The model file
|
|
for the LM124 opamp is listed below:
|
|
|
|
LM124
|
|
100M
|
|
600
|
|
100
|
|
1M
|
|
50%
|
|
|
|
|
|
First comes the component name followed by the input impedance and the output
|
|
impedance.
|
|
Next is the open loop gain in dB and the Gain Bandwidth Product GBW.
|
|
The tolerance refers to the open loop gain. Most opamps have a very high
|
|
open loop gain in excess of 100dB. Manufacures data sheets give conservative
|
|
values for open loop gain and it is well controlled.
|
|
Opamp model files MUST have the extension .AMP.
|
|
|
|
|
|
|
|
Hybrid PI Model
|
|
|
|
The Hybrid Pi model for a Transistor is illustrated below:
|
|
|
|
|
|
|
|
____rbc____
|
|
b' | |
|
|
B----rbb-------o---o o----o--------o-----C
|
|
| | |____Cc___| | |
|
|
| | | |
|
|
rbe Ce rce gm
|
|
| | | |
|
|
| | | |
|
|
-----o------------------o---------
|
|
|
|
|
|
|
|
E
|
|
|
|
|
|
|
|
|
|
|
|
The symbols have the following meaning:
|
|
|
|
|
|
rbb = Base spreading resistance
|
|
rbe = Input impedance
|
|
rbc = Feedback Impedance (effect of Vce changes on Base modulation)
|
|
rce = C-E Impedance
|
|
Cc = Collector-junction barrier capacitance
|
|
Ce = Overlap diode capacitance
|
|
gm = Transistor Transconductance
|
|
|
|
|
|
|
|
|
|
|
|
If the CE 'h' parameters are known at low frequencies at a given collector
|
|
current Ic (see manufacturers data sheets) then the impedances can be
|
|
calculated in the following order:
|
|
|
|
|
|
|Ic| |Ic ma |
|
|
gm = ---- = --------
|
|
VT 26
|
|
|
|
|
|
hfe
|
|
rbc = ---
|
|
gm
|
|
|
|
|
|
rbb = hie - rbe
|
|
|
|
|
|
|
|
rbe
|
|
rbc = ---
|
|
hre
|
|
|
|
|
|
1 1
|
|
rce = ------------- where gbc = ---
|
|
hoe-(1+hfe)gbc rbc
|
|
|
|
|
|
|
|
The capacitance Cc is the measured CB output capacitance with the input
|
|
open (Ie = 0), and is usually specified by the manufacturers as Cob.
|
|
|
|
Ce is experimentally determined from a measurement of FT, the frequency
|
|
at which the CE short-circuit current gain drops to unity.
|
|
|
|
gm
|
|
Ce = ------- PI = 3.14159
|
|
2*PI*FT
|
|
|
|
|
|
Typical values for a Hybrid PI model at room temperature and for Ic = 1.3mA
|
|
are
|
|
|
|
gm = 50mA/V rbb = 100 ohms rbe = 1k rbc = 4Mohm
|
|
|
|
rce = 80Kohm Cc = 3pF Ce = 100pF
|
|
|
|
|
|
Appendix B - Upgrade Utility
|
|
|
|
The utility program upgrade.exe is supplied to allow users of earlier
|
|
versions of aciran to convert their circuit files into the new format
|
|
used by aciran V3.1.
|
|
|
|
Previous circuit files had the extension CCT. The new circuit files
|
|
contain more information and are not compatible with earlier formats.
|
|
To distinguish them they have the extension CIR.
|
|
|
|
The new circuit files hold transistor collector current values, and
|
|
all the config information to save the user having to re-enter config
|
|
every time a circuit was loaded.
|
|
|
|
Any attempt to use the old circuit files by simply re-naming them
|
|
will result in program failure. The utility upgrade should be used
|
|
as follows.
|
|
|
|
At the dos prompt type:
|
|
|
|
upgrade <FileName> <CR>
|
|
|
|
Upgrade will read the circuit file into memory, perform the necessary
|
|
conversions, and create a new circuit file on disk, in the current
|
|
directory, with the same name, but with the extension CIR.
|
|
|
|
Upgrade can accept wildcard characters such as ? or *.
|
|
|
|
You could convert all your files in the current directory by simply:
|
|
entering
|
|
|
|
upgrade *.* <CR>
|
|
|
|
Upgrade applies default config parameter information into the circuit
|
|
files. This gives the following setup.
|
|
|
|
The next time you load the circuit and make modifications to the config
|
|
parameters these will be saved when you save the circuit.
|
|
|
|
THE END.
|
|
|