Why would a wall-wart design have an external FET driving an external high-voltage transistor? A decade ago, Paul Rako picked the brains of some of the top people in the industry to find answers. When ...

It used to be a rite of passage to be able to do the math necessary to design various bipolar transistor amplifier configurations. This doesn’t come up as often as it used to, but it is still a good ...

The circuit in Figure 1 sinks a constant current (ICE3) through Q3’s collector and emitter. This design is balanced so changes in Q3’s base-emitter voltage (VBE) don’t affect the current sink’s ...

Immediately, I learned that the common base configuration gain was 6db lower than the common emitter. This blew my mind. Then I started checking input resistance and was shocked at how low it measured ...

PartSim is used in this example to simulate the Common Emitter Amplifier. The base bias voltage is set with the voltage divider arrangement. The input signal is amplified by the 2N2222 NPN transistor.