Path: utzoo!news-server.csri.toronto.edu!rutgers!usc!elroy.jpl.nasa.gov!ames!vsi1!teda!ardai
From: ardai@teda.UUCP (Mike Ardai)
Newsgroups: sci.electronics
Subject: Re: IBM Power Supply - quick question
Message-ID: <21952@teda.UUCP>
Date: 11 Mar 91 15:28:33 GMT
References: <1991Mar10.173827.1690@ncsu.edu>
Distribution: usa
Organization: Teradyne EDA, Inc.
Lines: 21

In article <1991Mar10.173827.1690@ncsu.edu> bcasper@eos.ncsu.edu (BRIAN  CASPER) writes:
-I'm building a project and using an old XT power supply for a source.

-On P8, I think pin 1 is labeled "Power Good".  What is this for?  

Power good is a signal generated by the supply that is supposed to tell the
rest of the system that the AC power is present.  This is used to write-protect
the clock and CMOS ram (on AT's) on power failures to prevent spurious 
writes.  

XT supplies make good supplies for projects, but make sure you have enough 
of a load on it or it may shut down.

/mike



-- 
\|/  Michael L. Ardai   Teradyne EDA East
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