[sdiy] CA3140S vs. CA3140AE

[Magnus Danielson]

From: carlile at ece.utexas.edu
Subject: [sdiy] CA3140S vs. CA3140AE
Date: Fri,  3 Dec 2004 01:25:23 -0600
Message-ID: <1102058723.41b014e345e6a at connect.ece.utexas.edu>

> Can I substitute a DIP CA3140AE for a metal can CA3140S in an old synth?

Yes.

> I need to remove the CA3140S to clean some pretty bad corrosion around it..
> but I'm worried about damaging it by desoldering/resoldering it.  I'm trying
> to find the datasheets online, but not having any luck.  Is it the same thing
> w/  same pin out in just a different package?

The pin numbers are the same. The Tab is pin 8 and the top-view assignment is
the same.

However, you should not have to worry about that if you desolder it properly.

My trick for desoldering is fairly easy. Start of with soldering new solder
onto the joints. This way you break through the oxide layer which has bad
heatconduction. Doing it this way avoids "chargning" the chip with heat and
also lowers the damage to the card. Once you have a break-through you just feed
some more solder onto the joint and then stops and leave it too cool of. Next
pin same thing. Breaking through this was is very efficient. Then when all pins
are done you let it cool off and then you go for the actual desolder work,
preferably with a tin sucker, or that is at least what I use. You usually clean
up pretty easy on one-sided boards. If you have a residue tin-bridge, it might
be hard to raise the temperature on that part only... so apply tin again so you
get a larger body of tin again and the desolder it again. Double-sided cards
is a bit harder due to the through-hole plating, but resistors and caps is
easier with those boards.

Cheers,
Magnus