Problem

How can I change default digital power/ground pin voltages for various logic families including TTL, CD4000, ECL 10K and ECL 100K?

Solution

To specify custom power supplies place one of the digital power supply parts from SPECIAL.OLB library as mentioned below:

CD4000 power supply : CD4000_PWR

TTL power supply : DIGIFPWR

ECL 10K power supply : ECL_10K_PWR

ECL 100K power supply : ECL_100K_PWR

Listed below are steps done with DIGIFPWR but the steps are same for each of the above mentioned power supplies:

1. Place the digital interface power supply, DIGIFPWR from the SPECIAL.OLB parts library.

2. Double - click on the Voltage property and change it from 5V to desired voltage say 10V.

3. Select the DIGIFPWR part - right mouse click - Edit Properties. Select the Pins tab.

3. Find the pin property PSpiceDefaultNet.Change the existing power pin, "<VDD_Node>" to something like Vpwr, and the existing power pin, "<VSS_Node>" to something link Vgnd.

4. Edit each digital part you have placed on the schematic and change the PSpiceDefaultNet pin properties to match the pin names by doing below mentioned steps:

a) Double - click on say 74163 part and select the Pins tab at the bottom of window

b) Change the PSpiceDefaultNet property for the VCC net to Vpwr

c) Change the PSpiceDefaultNet property for the GND net to Vgnd

5. Repeat steps 4a) - 4d) for all additional digital parts