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Guide to replacing EPROMs with EEPROMs

eharmon

Well-known member
I much prefer EEPROMs over EPROMs; when tinkering the constant cycle of waiting for some chips in the UV eraser just gets annoying. But every time I need more chips I forget what the equivalents are, so I finally took my random notes and compiled it into a single page you can use to find what chips to replace your EPROMs with:


Let me know if you have any suggestions! I tried to cover the most common 27C DIPs found on Mac parts to start.
 

motosega

Member
What about 27c010, 27c020 and 27c040?

I never found direct replacements

27c040 EPROM and 39sf040 EEPROM have a slightly different pinout, which will require some bodge wires...
 

eharmon

Well-known member
What about 27c010, 27c020 and 27c040?

I never found direct replacements

27c040 EPROM and 39sf040 EEPROM have a slightly different pinout, which will require some bodge wires...
I definitely need to get to adding the larger sizes. For a 27C010 you can use a Winbond W27C010 or SST SST27SF010. Generally both of those lines are compatible with larger memories.

IIRC all the 39SF line is just a bit off JEDEC, unfortunately.
 

eharmon

Well-known member
Since I was real bored last night, I went ahead and updated to add the larger DIP EPROMs.

As far as I am aware, below 27C64 there are no EEPROM/Flash replacements, so I haven't bothered adding them.
 
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