Date   : Sat, 28 Apr 1984 20:23:36 EST
From   : David Towson (CSD) <towson@Amsaa.ARPA>
Subject: Re: Check your Delta Products/U.S. Micro Sales 64k DRAM boards

Added note:  The problem described by Mark may be VERY SERIOUS if the board
uses 4116 type DRAMS.  (I am not familiar with the board.)  If this is the
case, and if the capacitor mentioned degrades enough to cause loss of the -5V
supply, the result will be immediate and catastrophic failure of ALL of the
dynamic RAM chips.  This is why the power supplies for 4116 RAMs must be
properly sequenced so that the -5V comes up first and goes down last.  If the
board in question does not use 4116's, perhaps someone else can comment about
whether the same vulnerability exists.


Dave
towson@amsaa.arpa