A Zen/Schade-inspired driver for the two output devices. With PP, current can be set lower than SE for the same Pout. Could this go very wrong?
The choke could be substituted by a voltagecontrolling AC-CCS. And how the floating bias voltage should be arranged I don´t know. Global feedback shouldn´t be needed as the PP SF is 100%feedbacked already.
This was just a fantasy in the car on my way home from work today....
The choke could be substituted by a voltagecontrolling AC-CCS. And how the floating bias voltage should be arranged I don´t know. Global feedback shouldn´t be needed as the PP SF is 100%feedbacked already.
This was just a fantasy in the car on my way home from work today....
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Nice idea!
I would prefer using a DN2540 instead of a sk170 j-fet. The Supertex DN2540 can run a 100 - 200 mA.
Why not a White cathode follower type of output arrengemant? I dont like mixing N and P devices as complimentary pairs. The output should run in class A anyways to lower distortion...
I would prefer using a DN2540 instead of a sk170 j-fet. The Supertex DN2540 can run a 100 - 200 mA.
Why not a White cathode follower type of output arrengemant? I dont like mixing N and P devices as complimentary pairs. The output should run in class A anyways to lower distortion...
Did some adjustment to the circuit above. Now the driver is a JFET mini-Zen with an AC-CCS that controls the drain-voltage. This way we can also simplify the PP-follower by getting rid of the floating bias supply.
By using a PP-follower we also get an environment friendly simple amp that theoretically only needs 50% standing current compared to a standard SE SF. Or with (std) 2A we should get an amp with more muscle for lowZ loads.
By using a PP-follower we also get an environment friendly simple amp that theoretically only needs 50% standing current compared to a standard SE SF. Or with (std) 2A we should get an amp with more muscle for lowZ loads.
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Hey Woody,
A current source wouldn´t fix a stable voltage. This one is a gyrator with fixed and stable midpoint voltage for the outputstage. Also the MOSFET in the gyrator helps tempcomp, so that one is undercontrol(I hope). I get indications of -100mA from 25-100 degrees C.
A current source wouldn´t fix a stable voltage. This one is a gyrator with fixed and stable midpoint voltage for the outputstage. Also the MOSFET in the gyrator helps tempcomp, so that one is undercontrol(I hope). I get indications of -100mA from 25-100 degrees C.
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