Quasi Complementary ECX10N20 Amplifier with good performance

I started this thread for IRFP240 Quasi: https://www.diyaudio.com/community/threads/quasi-irfp240-amplifier.428495/
Now I use another MOSFET transistor for better qualities.
I use Exicon Lateral ECX10N20 for this thread.

The benefits are three:
1. Somewhat less distortion, THD 0.005%
2. Higher max output, 25 Watt in 8 Ohm
3. No need for MOSFET protection diodes, are already built in

Here is the schematic. Enjoy 🙂
Quasi ECX10N20 24V_01.jpg
 
lineup, you do not specify at what power the distortion is given. Also, you are not looking at my pictures carefully. Look at the transistor currents. It can be seen that the circuit is very asymmetrical, one of the transistors works almost like a current generator with a load power of 1 watt. The upper transistor won't close!


1749641090493.png


In order to get 25 watts of output, I increased the input signal 5 times. I didn't get 25 watts, the circuit was limited.

1749642090659.png
 
There is a serious problem with MOSFETs used like your U4 & U2.

When overloaded at HF, U2 gate is discharged VERY slowly and can't turn off. The U2 & the amp will die and release the Holy Smoke.
Actually, it is a less issue for the most mosfets comparing to BJT. Especially not an issue for the lateral ones.
For BJT, it is pretty common to use 100 Ohm bleeding resistor for one pn voltage drop.
 
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There is a serious problem with MOSFETs used like your U4 & U2.

When overloaded at HF, U2 gate is discharged VERY slowly and can't turn off. The U2 & the amp will die and release the Holy Smoke.
Actually, it is a less issue for the most mosfets comparing to BJT. Especially not an issue for the lateral ones.
For BJT, it is pretty common to use 100 Ohm bleeding resistor for one pn voltage drop.
Why don't you try it and see with either lateral or vertical MOSFETs.

Build it as shown, feed 20kHz at full power into an 8R load, and just turn up the volume a bit. Discharge of Holy Smoke isn't subtle.
 
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