Instrumentation amplifier input, inverted mode, nothing extraordinary, everything right. Should work and sound good.
Gerbers are ready if any interest.
Gerbers are ready if any interest.
Hmm, that simulates very well, -120dB or so, although I get a couple of zener diodes without models.
I have said that it is nothing extraordinary, but it have two quite unique features though.
First one is instrumentation amplifier input. I used it a while. The reason, it offers rather good stability and low distortions as plus. Hence you noticed it through simulations.
Stability under heavy loads is the main concern.
Not to mention great flexibility of use.
The second one...
First one is instrumentation amplifier input. I used it a while. The reason, it offers rather good stability and low distortions as plus. Hence you noticed it through simulations.
Stability under heavy loads is the main concern.
Not to mention great flexibility of use.
The second one...
Attachments
The second one is one very nice function hidden in bias circuit.
In fact, bias voltage is tracking output amplitude, proportionally increasing. Resulting in much reduced charging demand when switching outputs.
On impedance of 8R or higher it keeps it from closing at all. On 4R it closes but very gently.
So, lower resistance and greater need for power will close output transistor, let it rest until new half period. Altogether, close to A class performance
for only a fraction of power. Only a little bit bigger heat sinks.
In fact, bias voltage is tracking output amplitude, proportionally increasing. Resulting in much reduced charging demand when switching outputs.
On impedance of 8R or higher it keeps it from closing at all. On 4R it closes but very gently.
So, lower resistance and greater need for power will close output transistor, let it rest until new half period. Altogether, close to A class performance
for only a fraction of power. Only a little bit bigger heat sinks.
Attachments
So, here are the gerbers for those who want to make Compacto.
All the questions about op amps and compensation variations are welcome.
All the questions about op amps and compensation variations are welcome.
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Very nice, this is the sort of thing I have been looking for in designs.
Regards,
Alex
A couple questions....
What psu +/-V is needed for Compacto?
Suggested C2922/A1216 replacements?
Could you revise the gerbers to include clearly labeled Input, Output, +Vcc, -Vcc and GND pads?
Thanks!
What psu +/-V is needed for Compacto?
Suggested C2922/A1216 replacements?
Could you revise the gerbers to include clearly labeled Input, Output, +Vcc, -Vcc and GND pads?
Thanks!
Any PSU in range +/-30 until about +/-80V will do. We only have to care about heat and to ensure about 3mA for D1/D2 zeners.
Outputs are simulated with 2SC5200/2SA1943 and MJL4281/MJL4302 models and works like drop in replacement. That makes me believe
that the circuit is not highly sensitive on what is hooked for outputs. Of course, for some other pairs minor adjustment could be needed. No problem.
About gerbers, are here to be improved with good ideas, I'll place the labels and attach it here latter. 🙂
Outputs are simulated with 2SC5200/2SA1943 and MJL4281/MJL4302 models and works like drop in replacement. That makes me believe
that the circuit is not highly sensitive on what is hooked for outputs. Of course, for some other pairs minor adjustment could be needed. No problem.
About gerbers, are here to be improved with good ideas, I'll place the labels and attach it here latter. 🙂
