How to choose a pass element for the Jung Super Reg type circuit?
I am designing one with:
precision, ultra low noise voltage reference
--> rail-to-rail, ultra low noise op-amp
--> pass element
Nothing special here really. How do one determine which pass element to use (low voltage and low current requirement)?
Is very low noise a requirement of the pass element? If so, I am thinking that I can parallel a bunch of super low noise JFETs as pass element.
I am designing one with:
precision, ultra low noise voltage reference
--> rail-to-rail, ultra low noise op-amp
--> pass element
Nothing special here really. How do one determine which pass element to use (low voltage and low current requirement)?
Is very low noise a requirement of the pass element? If so, I am thinking that I can parallel a bunch of super low noise JFETs as pass element.
Hi,
does Jung have a current limiter?
Then you choose to suit either 5v * 60mA = 300mW dissipation,
or 5v * short circuit current = BIG dissipation.
The first option allows you to choose any BJT with a Pmax of about a watt with a clip on heatsink in case your fuse does not blow.
The second option means choosing a med power BJT with hi current capacity and large enough heatsink to prevent destruction until the fuse does blow.
I don't think that low noise BJTs matters in your context.
does Jung have a current limiter?
Then you choose to suit either 5v * 60mA = 300mW dissipation,
or 5v * short circuit current = BIG dissipation.
The first option allows you to choose any BJT with a Pmax of about a watt with a clip on heatsink in case your fuse does not blow.
The second option means choosing a med power BJT with hi current capacity and large enough heatsink to prevent destruction until the fuse does blow.
I don't think that low noise BJTs matters in your context.
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