[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: SSTC- feedback vs. none
Original poster: "K. C. Herrick" <kchdlh@xxxxxxx>
For the record, referring to my posted simulation circuit
Half-br_res-pri.jpg, when I add Schottky diodes across the bipolar
transistor base:collector junctions, change resistors R3 and R11 to 8
ohms, and then add the same resistances in series with the Q5 and Q2
collectors...I get perfect IGBT switching at the primary current
zero-crossings. The 4 resistors act to tweak turn-off & turn-on
delays as appropriate. The Schottkys reduce the delay in TX1 by a
hundred ns or so but the ones whose model I happen to have (1N5711s)
still exhibit 250 ns of turn-off time.
Even though this is only simulation, it's "food for thought".
KCH