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From: Joerg <news@analogconsultants.com>
Newsgroups: sci.electronics.design
Subject: Re: power supply discharge
Date: Sat, 28 Sep 2024 22:28:07 -0700
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On 9/27/24 8:07 AM, john larkin 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.
> 

Often the only internal load is the resistive divider for the regulator 
loop feedback.


> 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 have some. They drop very slowly when there isn't much load on the output.


> I'm designing some programmable multi-channel power suplies and that
> is one of many tangled issues in the project.
> 

A synchronous buck architecture should work quite well if you need to 
slew fast. I've used that on a driver that had to modulate a hard 
capacitive load at several kHz and above 100V.

-- 
Regards, Joerg

http://www.analogconsultants.com/