Wall warts are indeed an economical supply for many projects, but I have so
many of them in behind my stereo stand (and of course, they are too wide
for one slot on the power bar), that they almost take up more space than
the equipment they power.

I realize they eliminate the designer's need to get safety approval for
their hardware, and sometimes the device being powered is just too small
for an internal P/S, but why doesn't someone sell reasonably priced
"enclosed" PSU's that can be designed into the case of the equipment being
powered.  This strategy allows devices to get automatic approval for
telephone devices by using a pre-packaged and approved interface module.
 Why not pre-approved simple PSU's.  And I am not talking about those
commercial/industrial regulated supply modules that cost more than the
project.  Something unregulated, maybe even unrectified or filtered.  And
if the AC connection is the issue for safety, a power cord could be
'moulded' in, or the module could be designed to mount on the rear panel of
the project, with an AC receptacle (2 or 3 pin) and maybe a fuse socket
exposed on the back.

Just my opinion, excuse the rant.


Martin R. Green
elimar@bigfoot.com

----------
From:   Harold Hallikainen[SMTP:haroldhallikainen@JUNO.COM]
Sent:   Wednesday, September 03, 1997 4:09 PM
To:     PICLIST@mitvma.mit.edu
Subject:        Re: PIC power supply ...

        I think a "wall wart" is a very inexpensive way of getting power
for a PIC.  I've now got several products that use a 12V, 500mA unit
driving a 7805 regulator.  I think the wall warts are about $5 or less in
reasonable quantities.
        If you can put up with a nonisolated supply, consider the Maxim
MAX600, 601, 602, 610, 611, 612.  Info should be available at
http://www.maxim-ic.com  .

Harold