On an unrelated note, I bought those transistors to drive a flyback transformer as replacements for some more expensive MOSFETs. I wanted to see how BJTs would compare to MOSFETs in this application. Those were dirt cheap so I thought I'd give them a try. I was disappointed in the results.
Is there much I can do to reduce the Vce voltage and really drive them hard into saturation? I tried making a darlington but quickly found out that unless I use 2 of those transistors, then the small one will die (due to high voltage transients in flyback operation). Using 2 of them defeats the cost benefit of my favorite FTP33N25 MOSFET (a modern more-or-less equivalent to the IRFP250N with simalar ratings)
Interestingly, the TIP120 gave me amazing results!!!! (nice fat juicy white arcs, almost as good as the MOSFET), For about 2 seconds, till' it died.
So I know of the darlington configuration, and the complementary pair, and after asking this question on Instructables, and I did receive a very interesting configuration shown below, but other than that, what other classic or common BJT circuits exist for high power switching?