High Gate resistor value very unstable with Vertical mosfet in CFP.
Driver Current rating also very high at high frequency , even though assumed low.
Not like lateral, with typical high values for gate.
540 only need 33 to 47 ohms
Use fast 7 to 15 watt driver
Like high speed " Video" Bjt transistor
typical 2SA /2SC KSA/KSC 1381 / 3503 Transistor.
As with any CFP it usually takes a big hit on bandwidth to make it stable
and not ring. Higher THD for high frequency is normal tradeoff.
With multiple output devices any CFP is at risk.
Not good topology for high power.
Only fun for low power amplifier with single pairs if you want low THD.
Even in simulation is a barrier I have hit with Mosfet/CFP
high power is possible just lots of compensation to make work.
Use normal VI limiter. If 4 ohm load
VI limiter set to kick in at 1 or 2 ohm
No early trigger. Problem again VI limiter very unstable in CFP
Especially fancy slopes with capacitor, just barfs ringing in output.
CFP no good for high power or multiple output pair.
Current limit is Mosfet, to much current blows like fuse.
DC protect save 3000 dollar speaker, Mosfet 1 dollar
Driver Current rating also very high at high frequency , even though assumed low.
Not like lateral, with typical high values for gate.
540 only need 33 to 47 ohms
Use fast 7 to 15 watt driver
Like high speed " Video" Bjt transistor
typical 2SA /2SC KSA/KSC 1381 / 3503 Transistor.
As with any CFP it usually takes a big hit on bandwidth to make it stable
and not ring. Higher THD for high frequency is normal tradeoff.
With multiple output devices any CFP is at risk.
Not good topology for high power.
Only fun for low power amplifier with single pairs if you want low THD.
Even in simulation is a barrier I have hit with Mosfet/CFP
high power is possible just lots of compensation to make work.
Use normal VI limiter. If 4 ohm load
VI limiter set to kick in at 1 or 2 ohm
No early trigger. Problem again VI limiter very unstable in CFP
Especially fancy slopes with capacitor, just barfs ringing in output.
CFP no good for high power or multiple output pair.
Current limit is Mosfet, to much current blows like fuse.
DC protect save 3000 dollar speaker, Mosfet 1 dollar
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On fast , off slow.
Use driver degeneration to make high frequency square wave on time/ slew rate same as off slew rate.
If not ideal for THD the approach or idea to use different Mosfet likely good idea.
I have made fun amplifier with 540 very durable.
Difficult to drive at high frequency.
Use fast higher current driver than needed, Regardless if easier mosfet to drive.
Ft of BJT will still remain high if overkill.
Why I like 3503 /1381
Use driver degeneration to make high frequency square wave on time/ slew rate same as off slew rate.
If not ideal for THD the approach or idea to use different Mosfet likely good idea.
I have made fun amplifier with 540 very durable.
Difficult to drive at high frequency.
Use fast higher current driver than needed, Regardless if easier mosfet to drive.
Ft of BJT will still remain high if overkill.
Why I like 3503 /1381