MVS MV1B/1C battery replacement

[Big_P Big_p]

Some photos of my battery blaster installed, still working well 2-3 months later

 

[Big_P Big_p]

Just designed one of these up for the PGM too as I need to replace the original battery on mine.

 

[maki]

I reckon the FM1808B are drop in replacements
https://www.mouser.de/datasheet/2/196/Infineon_FM1808B_256_Kbit__32_K_8__Bytewide_F_RAM_-3361599.pdf

the SRAM datasheet
https://www.alldatasheet.com/datasheet-pdf/view/101650/SONY/CXK58256.html

pinout is the same no?

Just some feedback, I've tried FM1808-SG and FM18W08 on a MV4FS, neither work :/

 

[arcadecollector]

FM18xx: These chips need CE and OE pulsed low together. CE kept low all the time does not work at these ICs

FM28V020-SG would be an option to go! 3.6V max supply