I would say quad or hex, rather than dual. You can see it by finding those six sets of transistors, three on each side, each with the same sets of leads brought out to pins. Hex inverter, a-la 7404 but mil-spec? I agree that the asymmetrical package is very unusual. The density is so low that we should be able to suss out its function given a bit of study. Already the Vdd/Vss pins are identifiable at the center top and bottom. -Dave On 8/21/22 11:23, Douglas Crawford via vcf-midatlantic wrote:
A little more... https://imgur.com/f4noWuk
We have this on display under a microscope at VCF Mid-Atlantic museum.
It is strangely constructed to my eye. no lead frame or bond wires. Its build ON the leadframe. Its symmetrical, appears to be a dual something.
A mixed signal IC design collegue said: ---- That lead-frame is really weird. It seems to be some sort of flip-chip, but the leads don’t even line up from one side of the chip to the other! Never seen anything like it. The only other thing I would GUESS is that this is some sort of analog IC, probably bipolar. ----
-- Dave McGuire, AK4HZ New Kensington, PA