Power Buffer with Jfet IN and CFP OUT

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This universal buffer
works with a bootstrapped source follower
and a power stage CFP controlled by Wilson mirror:eek:
 

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Fixed bias cascode, no more no less.
If you would connect the 10kOhm of the cascode before the 22 ohm resistors that whould be a bootstrap. I would use Leds though supplied with CCSs because then the Fet drives a high impedance. Just connecting the fixed bias cascode before the 22 Ohm resistors put a burden on the Fets.
Anyway, your circuit has potential but can be improved.
Why the current mirror ? It makes the current in the emitter folower the same then the current in the collector follower. Maybe it would be better to run the collector followers on higher current then the emitter followers. That could be done with a scaled current mirror.
 
As i said, i would use 4 x red Leds instead of the 10kOhm in the input cascode. The Leds can be shunted with a 0.1uF.
Then substitute the 33kOhm with a degenerated JFet like J310 with 470 Ohm in the source.
That way the Fets drive a much higher impedance.
In the 33 Ohm then flows the Led current plus the Idle in the input J-Fets.
So maybe the 33 Ohm has to be reduced somewhat.
The circuit has to be simulated for optimum results and then build.
 
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