Electronic – Unknown (custom?) part

componentsidentification

The photo below shows a part that I am trying to find a specification for. I suspect that it is a microcontroller, and is part of a larger device that is essentially a timer. It clearly bears the National Semiconductor logo.

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However, I cannot find this device via searching, and it doesn't seem to fit into the National Semiconductor device naming conventions. Is it plausible that this might be a part custom-made by N.S. for the larger device manufacturer? Is this kind of thing done?

Best Answer

It is... I wouldn't say "common" per se, but not unheard of for semiconductor manufacturers to create or manufacture custom (ASIC) or custom-screened (although standard under the hood) parts for very large customers with no publicly trackable part number. At a cost, of course.