This made me look at the turn-off specs for the npn (a 2N2222A) and, for the first time I can remember, I noticed that the turn-off test circuit in the data sheet used a negative drive to the base.

Beat the Test challenge rooms in Transistor with our detailed guide full of tips and helpful hints!

This circuit uses pulsed current to check transistor hFE on an oscilloscope. The circuit creates the biasing conditions specified by the transistor’s manufacturer.

NPN transistors are key components in electronics, used as switches or amplifiers with three legs: base, collector, and emitter. Thyristors are semiconductor switches with three legs: gate, anode ...