formatting link
Look at that fT. One small part of your favorite new SiC gate driver, perhaps?
Don't know why they don't call out complements, but this looks close:
formatting link
Tim
- posted
6 years ago
Another fast transistor, good gate driver
Loading thread data ...
- Vote on answer
- posted
6 years ago
Bipolars are just never screaming fast switches [1]. That PNP is losing Ft fast above 1 amp. Ft = 300 MHz means a beta of one at 300 MHz, which is where a follower becomes useless. At 2 amps, Ft is way below 100 MHz.
Mosfets or better yet GaN fets could drive a big SiC a bunch faster.
The problem with GaN is that they are all n-channel, so making a pullup/pulldown gate driver can be a nuisance. TI and Peregrine have some half-bridge bootstrapped drivers for GaN, but they have high prop delays and maybe big minimum pulse widths.
This sort of thing is fun because it's so hard.
[1] especially the ones that are not EOL'd.-- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com