What mystery vintage chip is this?

[8008]

I bought a vintage EPROM UV Eraser. Inside of the device something was forgotten and fell around there, some beauty unknown chip.

A short google lens search brought nothing. Both for image and the text printed  "ST Microelectronics 901E/FC"

Because it was in an EPROM Eraser, it may contain an EPROM area. But it does not look like a common EPROM, because at leat three different sections could be
seen through the (dirty looking) glass window.

Maybe someone has an idea what this thing could be. I am just curious.

Dennis

[rsjsouza]

Any similar searches came up empty, but it might be a microcontroller with integrated EPROM - ST62 and ST63 had various versions with EPROM.

You could try to program it, but it might be a somewhat daunting task given it is a very old family
https://www.eevblog.com/forum/projects/found-a-nos-stash-of-st62e28-rom-mcus-how-were-they-programmed/

[mikeselectricstuff]

ST7 microcontroller - there was a 42 pin shrink-dip version of this. Usually OTP but I'm sure they did expensive UVEPROM versions for development

[ArdWar]

ST7 huh? I was thinking ST9 MCU with that code

[8008]

Thanks to mikeselectricstuff+rsjsouza, this looks really like being from range ST6-7 of controllers.
I could not get closer so far by checking images of these chips on Internet, despite there are many of such images.

What I did not see anywhere are these 6 white "boxes" on/in the silicon area, whatever that is.
I will try to clean that dirty quarz glass window, there is something like transparent glue on it preventing to see more details.

Many thanks for your expert view on the images!

@mikeselectricstuff: Hi Mike, I am proud that you were anwering my post. Have spent many great hours looking your videos in the last
~12 years, unforgotten your work with the large x-ray machine from some airport or the alarm beep when cutting that wire on a pacemaker ... :-)
 

 

[8008]

I could clean the glass and was able to look at the chip with my microscope. But its magnification is only about 40 or so, I see tiny characters on the die, but cannot read them (there is a "(c) 1992", I can read that, but not more). So I have only a sligthly better image of the die sections.