Sub 4164 for MB8118?

DarrenF

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I'm thinking I've got a bad MB8118 (or two... or three...). It's apparently the same as 4516, which is a 5-volt-only version of the tri-voltage 4116 16kx1 DRAM. The 4116 is commonly replaced by a 4164 in Williams applications (removing the +12 and -5 supplies, of course). So, it looks to me like the pinout & specs of the 4164 is the same as the MB8118, with the exception of the add'l address line... so it seems to me I should be able to just tie it low (or high) and it should work just fine.

Anyone ever actually try this substitution?
 
I may have meant 4517; I was going from memory.

Working on a Sega champion boxing; based on sg1000 console hw, apparently.
 
4516 is a ram as well but im not familiar with it. I do know the 8118 and 4517 are compatible.
The 8118's seem to be much easier to find.
 
Shouldn't have even mentioned it; not really relavent to the question at hand (8118 / 4164).

I'll try it out after the Super Bowl tonight and see what happens.
 
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I'll try it out after the Super Bowl tonight and see what happens.

FWIW, 4164s worked fine as a sub for MB8118s in my application. Had 3 bad ones (no D-out); replaced them and the video now looks good (well, as good as an cheapo analog conversion from composite color-difference signals to RGB video can be expected to look...)

Didn't even have to tie the unused address pin high or low; left it N/C. Must be an internal pull-down, cause they sit low and aren't connected to GND by the PCB as far as I can tell.
 
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