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From: john larkin <jl@glen--canyon.com>
Newsgroups: sci.electronics.design
Subject: Re: power supply discharge
Date: Fri, 27 Sep 2024 10:01:30 -0700
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On Fri, 27 Sep 2024 16:17:42 +0100, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:

>john larkin <JL@gct.com> wrote:
>
>> Given a benchtop power supply, you can turn the voltage up and then
>> down, and it goes down. Most have a substantial amount of output
>> capacitance, and can be driving an external cap too. So something
>> pulls the output down.
>> 
>> I guess that there are no standards for this, but I've never seen a
>> supply that just hangs high when it's cranked down.
>> 
>> I'm designing some programmable multi-channel power suplies and that
>> is one of many tangled issues in the project.
>
>A DC-coupled audio amplifier chip might work as a fully-controllable
>bi-directional power supply if your current and voltage requirements
>were fairly modest.  They have the advantage of being relatively cheap,
>well-protected and very fast (by power supply standards).  Some of them
>have the tab at input earth voltage, so they don't require isolation
>from the heat sink.

Unfortunately, it has to be a switching regulator.