Digital modelling application in PSpice

From the 23.1 release, you can model digital devices on the fly, with parameters as input by using the Modelling Application feature of PSpice.

To access the digital modelling application, follow these steps. 

1. Launch Capture and create a new project.
2. Open the schematic page and go to Place > PSpice Part > Modelling Application.

             This will launch the Modelling Application panel on the right side of the Capture window. 

3. Expand the Sources and Digital nodes to find the following new digital modelling components:
   1. Sources: Digital Pulse/Stimulus
   2. Gates: Buffer, Inverter, XOR, XNOR, OR, NOR, AND, NAND
   3. Flip-flops: SR, JK, D, T
   4. Latches: SR, D
   5. Digital Constant

As an example, If you launch an OR gate and flip-flop: Clocked SR – Set/Reset, You will find the following listed parameters that can be configured on the specific components to model their behavior.

• Logic parameters
  1. Number of Inputs/Outputs/Inverted Inputs
  2. Conditions (Triggering/Initial)
  3. Set/Reset (Level/Type) 

• Timing parameters
  1. Delay (clock to output/propagation/set/reset)
  2. Setup/Hold time 

• I/O parameters
  1. Threshold
  2. Hysteresis width
  3. Resistance (input/output)
  4. Maximum Voltage (input/output)

An example of the OR / NOR gate input window is shown below:

Team DesignTech

Cadence Design Systems