ALL MOSFET Amplifier.
THD at 1 Watt is 0.0008%
Harmonics shows most H2 and a bit H3.
Output should be at 17.9V and the bias is 1.20A.
Max output is like 18 Watt.
Tranformer should be 2x15VAC or 30VAC for like 40VDC supply.
Enjoy!
THD at 1 Watt is 0.0008%
Harmonics shows most H2 and a bit H3.
Output should be at 17.9V and the bias is 1.20A.
Max output is like 18 Watt.
Tranformer should be 2x15VAC or 30VAC for like 40VDC supply.
Enjoy!
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I notice you don't use source resistor such as 0.22 Ohm usually. U5 could be BD140 so that you can do thermal coupling to the output transistors.
I prefer tying C2 from the output stage instead of VAS. You want R1 and R4 see the same amount current changed. The C2 on VAS will make the current imbalanced.
I prefer tying C2 from the output stage instead of VAS. You want R1 and R4 see the same amount current changed. The C2 on VAS will make the current imbalanced.
I have made the changes you suggested.
I took 0.1 Ohm source resistors.
Performance is still the same. THD 0.0008%
I took 0.1 Ohm source resistors.
Performance is still the same. THD 0.0008%
I added an output 24V Relay.
There is a delay of 20 seconds while the output capacitor is charged.
That is what the R17 270 Ohm is for.
There is a delay of 20 seconds while the output capacitor is charged.
That is what the R17 270 Ohm is for.
Thanks @thimios for asking.Thanks for another good small amplifier!
Is a pcb available?
No, there is not any PCB so far.
And I have not built this amplifier. I only have simulated it with SPICE.
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