[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


Original poster: "Steve Conner" <steve.conner@xxxxxxxxxxx>

>What is better to use in a Solid State Tesla Coil: a bipolar transistor
>push-pull stage (as it is on Richie's site circuit), or MOSFET drive IC's
>(TL4422 fnd TL4421)?
>What is the difference?

Most SSTC builders I know of seem to use the MOSFET driver ICs, for
convenience. It is possible to make a bipolar transistor driver that
performs as well as a driver IC, but you need to use special high-current
high-speed transistors like the ZTX851 and ZTX951 from Zetex or Fairchild.
The ZTX*** units are specially designed to have a high gain at high
currents, and fast switching times.

If you are using MOSFET driver chips, you might like to try the UCC37321 and
UCC37322 which are more powerful (and maybe cheaper) replacements for the
TC4421 and TC4422.

There is no reason why you shouldn't use MOSFET driver ICs to replace the
transistors in Richie Burnett's SSTC circuit. You may have trouble replacing
MOSFET driver ICs with discrete transistors though- a discrete transistor
stage needs a lot more current to drive its input than an IC does. (if the
transistors have beta of 100 and you want 9A out then you need to put 90mA

Steve Conner