PCB Design Blogs

When you are designing a schematic, you want to focus on the accuracy and performance of the circuit, and not spend time looking for and comparing various components on vendor websites. The integrated part search and placement feature in the OrCAD® Capture-PSpice® A/D solution offers an efficient method to find the perfect part.

A part that you can simulate must have a simulation model associated with it to describe the part’s electrical behavior. This model can be defined in a model library, built into PSpice A/D, or built into the part (for some kinds of analog behavioral parts).

To find the right component for your design, you can use any of the following five ways:

1. Place Menu
2. PSpice Part Search
3. Modeling Application
4. Place Part
5. Search Providers

When you use the Place menu, PSpice Part Search, or Modeling Application, you can place PSpice parts directly on the schematic. This is because the simulation models corresponding to the parts get automatically included in your design.

On the other hand, with Place Part and Search Providers, you must place a part symbol and then associate the PSpice model to be able to simulate such parts. The part needs to have an associated model and property defined to simulate the part in PSpice A/D.

In this blog post, let’s explore these methods.

Place Menu

Using a component from the Place menu places parts with ideal model definitions, which define a basic set of model parameters. Choose Place – PSpice Component and you see a list of commonly used PSpice components from the following categories:

• Digital
• Discrete
• Passive
• Source

PSpice Part Search

In PSpice Part Search, you find all the PSpice A/D parts in one place. You can browse using part categories or library. And if you don’t remember which PSpice A/D library contains a specific model, you can always use the search function. Open the PSpice Part Search pane, specify a search string, and place the required part from the search results. To access PSpice Part Search, choose Place – PSpice Component – Search.

Alternatively, click Launch PSpice Part Search on the PSpice toolbar.

Modeling Application

If you need a model with specific parameters, use PSpice A/D Modeling Application. For the required device type, specify the parameter value from the datasheet and place the component associated with the newly generated model. All this without leaving the schematic entry interface of OrCAD Capture. However, with this method, you can generate models for a set of general-purpose devices. This interface provides a defined set of model parameters and an advanced user should either use PSpice Part Search or Model Editor to create a custom model.

To access the Modeling Application pane, choose Place – PSpice Component – Modeling Application.

Alternatively, click the Modeling Application icon in the PSpice toolbar.

Place Part

Choose Place – Part or press P on your keyboard to open the Place Part pane. In this pane, you can select one or more libraries to look for a part. This method is handy when you know the library (or group of libraries) where the part might exist. 

If you add libraries from either <installation directory>\tools\capture\library\pspice or <installation directory>\tools\capture\library\pspice\advanls, you get to add parts which are simulation ready. Alternatively, you can directly search for a part.

Search Providers

To add parts from Cadence-supported content providers, choose Place — Search Providers. Search for parts, symbols, footprints, and their corresponding 3D models from Cadence-supported content providers (external vendors) — SamacSys and Ultra Librarian, and then place them. You can also perform a free-text search for parts based on categories and use parametric filtering to select the component you need.

To make these components simulation ready, use the Associate PSpice Model feature after placing the desired component on the schematic.

You can also access PSpice.com to view and download a range of PSpice models, which are available from multiple vendors. 

So, these are the ways in which you can find the right part. Go ahead and experiment to find the method that best works for you. 

To know more…

The Searching and Placing Parts video shows how to use Place Part. See how Search Providers enables you to find the required part from the available vendors without leaving the design environment. And keep watching this space for more information on some of these methods.