In the early days, PNP bipolar transistors were common, but the bulk of circuits you see today use NPN transistors. As [Aaron Danner] points out, many people think PNP transistors are “backward” but ...

Offered in a 5-lead TO-264 package, the 15-A NJL1302D (pnp) and NJ3281D (npn) ThermalTrak bipolar power transistors incorporate an internal thermally matched bias diode to eliminate warm-up time, ...