Re: power supply discharge

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/