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Guide to replacing EPROMs with EEPROMs
Posted by: eharmon on 2023-10-28 20:50:50
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:

eharmon | Guide to EPROM Replacements

Suitable EEPROM and Flash replacements for EPROM chips
eharmon.net eharmon.net

Let me know if you have any suggestions! I tried to cover the most common 27C DIPs found on Mac parts to start.
Posted by: motosega on 2023-10-28 21:09:28
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...
Posted by: eharmon on 2023-10-28 21:32:51
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.
Posted by: eharmon on 2023-10-29 12:57:22
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.
Posted by: Phipli on 2023-10-29 13:01:59
@funnymike

You might want to pay attention to this thread.

Note winbond do some 27C010 chips that are electronically erasable - this makes them easier to handle because if you need to erase them, you don't need a UV lamp.

Something like this :

www.ebay.com

1PCS/5PCS W27C010-70Z W27C010-70 W27C010 Encapsulation:DIP-32 EPROM WINBOND | eBay

Find many great new & used options and get the best deals for 1PCS/5PCS W27C010-70Z W27C010-70 W27C010 Encapsulation:DIP-32 EPROM WINBOND at the best online prices at eBay! Free shipping for many products!
www.ebay.com
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