10 Apr
2013
10 Apr
'13
6:27 p.m.
On Apr 10, 2013, at 8:21 PM, Mouse <mouse at rodents-montreal.org> wrote:
Yeah, if you run some of the less intelligent ones with two low a
load, the duty cycle on the switcher shrinks to near zero, which
means lots of sharp pulses up/down next to each other on an
inductor. The end result is not nice. The smarter systems will
just hold off for a period if they detect an insufficient load;
the even smarter ones will switch in a dummy load automatically.
- Dave
Probably not
that particualr PSU, but I know that some of the smaller
DEC pSUs used on Qbus systems do not work correctly unloaded.
It wasn't a DEC PSU, but I once fried a PSU by running it with too
little load. (It was a Sun SPARCstation SLC or ELC, I forget which,
and I was using the PSU without the monitor load it was designed to
always drive - http://www.sunhelp.org/~mouse is a page I wrote up for
sunhelp.org which, among other things, mentions the experience.)