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.
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.
OK it's better connect the cascode as bootstrap,
a scaled current mirror? intresting!
can you edit the original schematic with your improvement?
Regards
a scaled current mirror? intresting!
can you edit the original schematic with your improvement?
Regards
The scaling can be done by putting resistors in the emitter feed of your Wilson.
For example a 100 Ohm on the left side and a 50 ohm on the right side.
Then the collector follower runs on double the current then the emitter follower of the Szikley pair.
For example a 100 Ohm on the left side and a 50 ohm on the right side.
Then the collector follower runs on double the current then the emitter follower of the Szikley pair.
Change the 10kOhm in the casdode to 4 red Leds in series.
Instead of the 22kOhm use J310 JFets with 470 Ohm source resistors to supply the less.
Connect the Leds BEFORE the 22 Ohm resistors, then you have your bootstrap, a driven cascode.
Instead of the 22kOhm use J310 JFets with 470 Ohm source resistors to supply the less.
Connect the Leds BEFORE the 22 Ohm resistors, then you have your bootstrap, a driven cascode.
With some more work this could be a nice power amp or preamp.
I will draw up how i whould do the input stgae but in priciple it should work.
I will draw up how i whould do the input stgae but in priciple it should work.
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.
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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