PSpice Schematic Capture
Guide
Starting a Project: In MS Windows go
to Start/All Programs/Cadence/OrCAD 16.3/OrCAD Capture CIS ,
then File/New/Project.
Name
the
Project,
select
‘Analog or Mixed A/D’, and browse to where you
want the file saved (there is no ‘save as’, so this is important).
Select ‘Create a blank project’.
Getting Parts: Go to Place/Part. You can type in the
first letters of what you’re looking for in the upper typing area. (It
may be necessary to 'Add Library' if the part you need isn't available.
For example, the analog library has standard passive components.)
Double clicking on the part name allows you to place it in your
schematic area.
Placing Parts: You should see your part move around when you
move your mouse. Click once to place a part. Right click/End Mode
will stop part placement.
Getting Ground: There are different grounds for different
applications, but we will use ‘GND_SIGNAL’ (note that is not
the same as GND_FIELD SIGNAL). Grounds can be found in Place/Ground,
or
by
clicking
the
ground
button on the right. Change
the ‘Name’ to 0 (zero) for all
grounds. (It’s easiest to change one, place it, then copy and
paste it, or just place all you need right away).
Rotating and Flipping: To rotate a part or flip it horizontally
or vertically, click on the part to highlight it, then right click to
see your options.
Connecting Parts: Go to Place/Wire. Clicking on one
node, then the other will connect the two. Clicking at any point in
between will create a connection point there.
Placing Probes: There are two buttons on the Capture window edge
that are the voltage and current probes. You can also Place/Part
and select the appropriate VPRINT or IPRINT (from the special libary).
Place a voltage probe
where you want to see the waveform.
Setting Up the Simulation: Go to PSpice/New Simulation
Profile. Give the profile a name. The simulation profile sets up
parameters for simulation, such as run time, step size, and simulation
type. Click on the Analysis tab. For straight dc calculations, select
‘Bias Point’ as the analysis type. To view waveforms that change over
time, select ‘Time Domain (Transient)’. For the latter case set the
time that the simulation will run and the number of points that will be
calculated (step size). For typical simulations for this class, good
values are 10ms for 'Run to time' and 10us for 'Maximum step size'.
Note that a run time that is too short will not allow you to see a
whole period of a waveform and too long a run time will make the plot
look like a bunch of noise. Too small a step size will result in the
simulation taking an eternity to complete, and too long a step size
will make your plots look jagged (which will cause problems with FFT
plots, when you use them in later courses).
Running the Simulation: Go to PSpice/Run. Or on the edge
of the capture window there is a button that looks like a ‘Play’
button. Nearby are buttons to edit your simulation profile and create a
simulation profile. Holding your cursor over a button will display what
the button does.
Dual Plots: In Probe, go Plot/Add Plot to Window, then Trace/Add
Trace, then select the waveform you wish to see.
Viewing Model Parameters: Double click on a part, scroll across
screen.