On Sun, 10 Jul 2005 21:16:38 +0200, Robert Hedan
<
robert.hedan@...> wrote:
> Hi,
> I've just uploaded a schematic of a 40V 3A circuit that I put together.
> I've thrown in every security measure I could find in the DigiKey manual
> as
> an exercise. The file is in FILES / Power supplies. This link may (or
> may
> not) work:
> <http://f1.grp.yahoofs.com/v1/MHDRQjmKCjHN8hORzw6Lxapg3rQLHR9sg4BZ8ePemrCIKl
> pX6E8d2Q1QnZ52WUfAGgpe1uV08UyZCt9sgF5IHEcaLLyziJI/Power%20supply/Drilling%20
> station%2040V%203A%20steppers.JPG>
> Please let me know if I have design flaws, is the fuse rating high
> enough,
> components in series instead of parallel or vice versa, suggestions for
> additional security measures, improvements in filtering, etc.
> This is my first power supply and I don't want to have problems with it
> in
> the future. I also want to make it as robust as possible. A separate 5V
> circuit will power the logic circuitry, this is exclusively for the
> steppers.
> Robert
>
You certainly have a few surplus parts in there ;-)
What's the inductor L1 for?
U2/3/4/5 are a mystery to me.
What is the EMI coil, what is the input? mains?
Putting caps in parallel to lower ESR is a nice idea, but usually you'd
only put one electrolytic and one ceramic. If you want to use several
electrolytic parallel instead that is a good thing, but usually you'd use
the same size. A very small electrolytic parallel with a big one is just
not changing anything, esp. if you have a ceramic cap too.
I dunno about your fuses, you certainly have a great many. I wouldn't want
to predict which one will trip first. Also, i wouldn't see the need.
What i would have done if i had to use a transformer supply and not a SMPS:
hot->fuse->(NTC)->primary1->primary2->neutral.
(ntc in case of toroid transformer)
sec->bridge rect. at least 20A->electrolytic cap 6800-10000u->voltage
regulator->cap 220u or more parallel 100n to 470n->polyfuse->out.
ST