The additional filtering was to isolate the input stage from big current bursts in the OPS.
But I'm no expert! 😎
But I'm no expert! 😎
It is a good buffer.
I tested with a good opamp as input and I let the output be 10Vp.
At 1kHz THD was 0.0003% ... that is -110dB.
I tested with a good opamp as input and I let the output be 10Vp.
At 1kHz THD was 0.0003% ... that is -110dB.
Optimized the resistors' value around the bias network.
Added degenerative resistors R29, R32 to Q5, Q6. This solves the transient current spikes. It also limits the current of Q7 and Q8.
Bode plot
Added degenerative resistors R29, R32 to Q5, Q6. This solves the transient current spikes. It also limits the current of Q7 and Q8.
Bode plot
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Hi again!
Spent some time with layout... first one unsuccessful, but here is a finished board.
Latest schematic for this PCB:
PCB:
Spent some time with layout... first one unsuccessful, but here is a finished board.
Latest schematic for this PCB:
PCB:
Last edited:
I bought some 10uF ceramic caps before, primary for audio input coupling.
I realize the voltage here is pretty low. They are perfect here.
The price before tariffs. The 16V version.
The 50V version is about double the price. The 16V version is enough here.
Keen to see you build working and any changes that result. Nice design