An introduction to the Cadence OrCAD program use for a simple schematic simulation.
From the Start Menu:
Select “All Programs”, then find the “Cadence” folder as shown below.
Select/Click the “OrCAD 16.6 Lite” sub-folder.
Select/Click on “OrCAD Capture CIS Lite” program.
Some items can be selected from the “Getting Started” panel in the center of the display;
however, it is recommended that the normal entry procedure is used by going to the upper
left corner and selecting “File”, then “New”, then “Project” as shown below.
When you have selected “Project”, the following panel will be displayed. In this panel
“Schematic” is selected. DO NOT use this selection unless only a schematic is wanted and not
a simulation of that schematic. Instead, select “Analog or Mixed A/D”. A project Name must
be assigned (at the top of the box) and a Location (at the bottom of the box).
When completed, it should look like the following box. Note that a location has been selected
that is not in any of the OrCAD program folders, but in a main “Files” area.
Click “OK” and the following panel will appear. If the “New” project is not based in full or in
part on another project, then select “Create a blank project” (at the bottom). If a copy of
some other completed project is wanted as the starting point for the new project, select
“Create based upon an existing project”, then select it from the “drop-down list or “Browse”
for the location of that project (it will have an “.opj” extension). Note that none of the original
project contents will be altered by any changes made to the new (copied) project. In some
cases a blank project might be the selection; however, in most cases the schematic will almost
always require a ground, so selecting the existing project “AnalogGNDSymbol.opj” will start
the schematic with a ground. (If you select the “blank project” option the ground will have to
be placed separately.)
When the selections are complete, click “OK”. The following display is for the “Create based
upon an existing project” with the “AnalogGNDSymbol.opj” selection, as shown in the panel
above. The following display will be presented (it has been cropped).
Open the subfolder “test one.dsn”, then subfolder “SCHEMATIC1” to see subfolder “PAGE1”.
It will look like this (cropped):
Then click on “PAGE1” and get the following display. Take a few moments to explore the top
toolbar drop-downs (File, Design, Edit, etc.). Note the toolbars below the top one. Pausing the
pointer over the item will tell you what it does. Also note the vertical toolbars on the right
(most of those are for more advanced schematics, except the ground and text options).
Texts and parts can be selected by clicking on them or by a “click,hold and drag” to enclose the
item. If a right click is done within the box or highlighted area, a menu of options appears
(Cut, Copy, Delete, Rotate, etc.). Try this with the text below the ground symbol and delete it
(either using the “Delete” key or the method described above. This action can be reversed by
selecting the “Edit” tab in the top toolbar and selecting “Undo Delete”. Select “Place ground
(G)” from the innermost vertical tab at the right, drag it and place it in the schematic, move
over a bit and place another one, then use the “Esc” key of the computer to stop further
placements. Now use one of the methods to delete those two grounds. Delete the text below
the other ground. And the display will look as follows (cropped).
Go to the top toolbar and select the “Place” tab, then the “Part” option. Note the panel at the
right, shown cropped below. Explore those part options for the various libraries shown.
In the “SOURCE” library “Part List”, scroll down to find the “VDC” option and select it, then use
either the “Enter” key from the keyboard or go to the top of the panel and click on the small
icon “Place part (Enter)”, found on the left of the “?” icon, and drag the part. When the part is
placed, use the “Esc” key to terminate the placement(s). If more than one was placed,
highlight the extras and delete them. From the “Analog” library select the “R” and place two
resistors in the schematic.
Now rotate one of the resistors (click on it, then right-click on the highlighted region and select
“Rotate”), then move the parts and text around until it looks like the following display. (The
“Place Parts” panel has been removed by clicking the very small “x” in the panel’s upper right
corner.)
The last part of the process is to “wire” the parts together. Do this by going to the “Place” tab
in the top toolbar, and selecting the “Wire” option. Use “click and drag” from part-tab to parttab for each connection. Use “Esc” to end the process. If a mistake is made, highlight it,
“Delete” and try again. If it is hard to see the circuit, “click and drag” a box around the whole
circuit, right-click in the highlighted area and select “Zoom In”. The display should be similar
to the following (zoomed in).
Double-click on each component value and edit each panel displayed for the desired numeric
values and information to be displayed. Select 10 volts for the source, 3kohms for R1 and
leave R2 as is. The display should be similar to the following. If some text is in the way,
highlight it and drag it to a better location. Note that the “ground” wire has been shortened.
If it is desired to display the bias voltages and currents after the simulation has been run,
select the “V” (Enable Bias Voltage Display) and/or “I” (Enable Bias Current Display) from the
toolbars at the top. Alternatively, they can be selected using the “PSpice” drop-down tab in
the top toolbar, then the option “Bias Points”. If the values displayed after simulating are in
the way, they can be individually deleted or moved, or they can be collectively turned off by
means of the “V” or “I”, etc., in the toolbar.
Select the “PSpice” drop-down tab from the top toolbar, then the option “Run”. If there are
problems, make sure that points aren’t “floating”, meaning not fully connected. Make certain
that the “o” above the ground is as shown above. To get back to the schematic, select the icon
in the desktop toolbar for the schematic as shown below.
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When done, the schematic should look like the following. Note that the Voltages and Currents
have been displayed and some have been selectively deleted.
Change the value of V1 to 12, R1 to 4k, R2 to 2k and run again. The results are displayed as.