21 Jan
1999
21 Jan
'99
1:55 a.m.
At 09:09 AM 1/21/99 -0500, Chris wrote:
At 07:07 PM 1/20/99 +0000, you wrote:
Thanks. This is what I guessed, and means the IC's have seen some third
party testing company. Some 2102 rams that I had bought "new" in tubes and
some from Godbout (S-100 memory cards) have the "ETC" stamp, so their
supplier had already gotten them this way, vs. direct from Intel.
Have seen the red enamel dots on IC packages as well, usually TTL.
-Dave
Hi all,
I have seen several plastic DIP IC's from the 1970's have a white ink stamp
on them that
say something like "ETC 4" on them. (Your number may vary) Most are Intel
RAM's, but some are Signetics or National TTL. Before I have seen them on
chips on boards, but have now bought a bunch of IC's new in tubes which also
have this stamp.
Has anyone else seen this and know what it means?
This is probably a mark from a company who tested the IC. Back in those
days, third-party outfits would often "burn-in" ICs before the company who
purchased them received them. The ICs were put under correct the correct
supply voltages and left in a closed chamber for many hours (24, 36, 72? It
varied.) Some IC distributors offered this extra cost service. It helped
make sure the chip would not fail prematurely when the end item was in
customer's hands. At Bausch & Lomb, when my ex-employer was still a
division of them, we had even the TTL and old RTL/DTL chips burned-in, not
just the expensive RAM, CPUs, etc. Some products from other B&L divisions
were used in medical labs and opthalmic labs and needed to be quite
reliable. Our division's products, used in an industrial environment,
benefited very nicely from tested ICs.