By Saumitra Raj Mehrotra1, Abhijeet Paul1, Gerhard Klimeck1, Dragica Vasileska2, Gloria Wahyu Budiman1

1. Purdue University 2. Arizona State University

This tool simulates a Bipolar Junction Transistor (BJT) using a 2D mesh. Powered by PADRE.

Launch Tool

You must login before you can run this tool.

Version 2.5 - published on 23 Jul 2014

doi:10.4231/D3BR8MH1H cite this

This tool is closed source.

First-Time User Guide View All Supporting Documents

    Structure Input deck Discrete BJT Input deck Minority Carrier characteristics Gummel Plot for npn Output Characteristics for npn BJT Beta Vs Ic



Published on


A bipolar junction transistor (BJT) is a three-terminal device constructed of doped semiconductor material and may be used in amplifying or switching applications. Bipolar transistors are so named because their operation involves both electrons and holes. Although a small part of the transistor current is due to the flow of majority carriers, most of the transistor current is due to the flow of minority carriers, and so BJTs are classified as “minority-carrier” devices.

This tool allows Bipolar Junction Transistor (BJT) simulation using a 2D mesh. It allows the user to simulate an npn- or pnp- type of device in common-emitter and common-base configurations. Users can specify the Emitter, Base and Collector region depths and doping densities. Also, the material and minority carrier lifetimes can be specified by the user.

Typical simulation run time LINEAR: ~ 2 minutes

Typical simulation run time DISCRETE: ~ 4 minutes

If you want to know more about the physics of the operation of BJT plese refer to the following slides:

BJT Operation Description

Example Problems for BJT:

BJT Theoretical Exercise

h-parameters calculation

BJT tool wish list :

Upgrading to include HBT simulations.

Improvements / modifications in subsequent version releases:

Powered by

PADRE (Pisces And Device REplacement) developed by Mark Pinto & Kent Smith at AT&T Bell Labs.

Sponsored by


Cite this work

Researchers should cite this work as follows:

  • Saumitra Raj Mehrotra; Abhijeet Paul; Gerhard Klimeck; Dragica Vasileska; Gloria Wahyu Budiman (2014), "BJT Lab," (DOI: 10.4231/D3BR8MH1H).

    BibTex | EndNote