Zener diodes are frequently used in level meters, voltage references, and overvoltage protection. Simulating accurate circuit behavior is critical in these applications; however, sometimes standard Zener diode models provided with SPICE simulation software don’t accurately reflect the component parameters. PSpice allows you to quickly define and create a SPICE Model for a Zener diode for a realistic simulation.
This quick how-to will provide step-by-step instructions on how to create models for Zener diodes in OrCAD PSpice to accurately simulate circuit behavior.
To follow along, download the provided files above the table of contents.
How-To Video
Creating a Zener Diode SPICE Model
Step 1: Open the provided design in OrCAD PSpice Designer.
Step 2: Select Place > PSpice Part > Modeling Application from the menu.
Step 3: In the Modeling Application, expand Diodes and select Zener Diode.
Step 4: Enter Dz for the Part Number.
Step 5: Set the Zener Voltage to 5 and the Temperature Coefficient to 2. Learn how to decipher a Zener Diode datasheet to determine the parameters required for SPICE Model creation here.
Note: You can choose whether the temperature coefficient is given in mV/°C or %/°C.
Step 6: Click Place to attach the component to your cursor.
Step 7: Click to place the diode in the circuit.
Running the Simulation
Step 8: Select PSpice > Run from the menu.
Step 9: View the simulation results. An output waveform with clipping is shown.
Modifying the Zener Diode SPICE Model
Step 10: Back in the schematic, right-click the diode and select More > Edit Source Component.
Step 11: Change the Zener Voltage to 3 and click Update.
Step 12: Select PSpice > Run from the menu.
Step 13: View the results. More of the waveform at the output has been cut.
Wrap Up and Next Steps
Quickly create SPICE Models for Zener diodes in your designs and simulate accurate circuit behavior with the modeling application in OrCAD PSpice. Test out this feature and more with a free trial of OrCAD. To learn more about deciphering a Zener Diode datasheet to determine the parameters required for SPICE Model creation, view our blog here.
