Anyone very familiar with PSPICE?

I am doing lab work in PSPICE version 8, not the version ( by Orcad. I am wondering if there is a way to change the parameter values of parts in the parts library. I need to change the Beta value of a transistor and the option is not availible in the basic settings of the transistor.

Anyone know how to do this?

I haven’t used *SPICE in ages, but I happen to have the manual handy. According to my manual, paramater BF is “ideal maximum forward beta”


To add to what N9IWP said, you’d have to get your hands on the actual SPICE model of the transistor you’re using. The “model” is a text file that contains all of the physical parameters of the device, in this case a transistor.

Are you using PSPICE in just drag-and-drop mode, or are you familiar with editing the text files generated by the GUI? Is changing the beta value specifically part of your assignment? If so, there ought to be someone in the lab who knows how to do it. If you’re just curious or experimenting, you’ll have to get your hands dirty. If you have PSPICE on your own computer, then you can probably find the files one way or another, but if you’re using a university machine, they’ll have the necessary files locked down.

Regardless, the exact way to change the beta value is going to depend on the specific transistor model you’re looking at. Almost certainly there won’t just be a parameter called “beta” that you can change. SPICE models tend to have their own set of parameters that don’t necessarily match up with the paramters used in hand calculations. In fact, there are many different flavors of SPICE models for the same kind of devices. They vary in complexity and accuracy.

One way would be to make you own transistor model leaving all the parameters the same except change the Beta .