29 Jun
2009
29 Jun
'09
11 a.m.
Tony,
I believe it is an AD891D Rigid Disk Data Channel Qualifier !! The datasheet
( PDF ) is 491K if you want me to send it to you.
I am absolutely sure you're correct -- many thanks...
If I'd thoguht of searching for 'rigid disk', I might well have found it
myself. Oh why can't there be standard names for these things :-).
And of course being an ECL chip means that the power lines appear to be
the wrong way round at first. But upon reading the datasheet (no need to
send it,, I've read it on datasheet archinve), I saw the bit about
running it from +5 and +12V. The input circuit shown seems to match up
with what I have too...
-tony