Discrete buffer notion

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Apologies to Joe Rasmussen and Allen Wright for this variation on the Super Linear Follower. But wondering if it might work with a BJT on top?

Sheldon
 

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Apologies to Joe Rasmussen and Allen Wright for this variation on the Super Linear Follower. But wondering if it might work with a BJT on top?

Actually, it is a variation of my Tower power stage.

No, such a way it will not work. You need to add some voltage on the base, instead of dropping it. Use one CCS fro + rail to base, and a resistor from base to output of the source follower.

Or, one Zener from output to base, and one resistor to B+

Tower-concept.gif
 
Thanks.

Quickly drew this up before going to bed, and thought I could eliminate the resistors. Somehow it didn't seem right, which is why I posted the question. Realize now, as Wavebourn notes, that I was looking at the voltage drop backwards. Sometimes tripped up on errors too obvious to see.

I like Lumba's LED approach, as it eliminates a cap, plus it lights up. Is there any advantage to a BJT in the top position, as compared to an FET? I guess I'd use a higher beta device than the 5551.

Sheldon
 
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