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From: liz@poppyrecords.invalid.invalid (Liz Tuddenham)
Newsgroups: sci.electronics.design
Subject: Re: power supply discharge
Date: Fri, 27 Sep 2024 16:17:42 +0100
Organization: Poppy Records
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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.


-- 
~ Liz Tuddenham ~
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www.poppyrecords.co.uk