@User: This is a work in progress of reverse-engineering the SkyWater SONOS flash memory array. How easy/hard would it be to get this to work in OpenRAM? It is relatively more simple than an SRAM, because reading just involves detecting a current over a threshold. It needs a layer of analog muxes to set the programming and erase voltages, and outside of that it just needs row and column decoders. A first cut can probably manage without a high voltage charge pump---but it does need to reach +6.7V and -3.8V during program and erase.

Let me take a look soon..

in the sonos_array.mag it looks fairly unlabelled: is that something I could help with?

Sure; I'm just putting it out there because I don't have a whole lot of time to work on it myself. It's a pretty simple cell of two transistors. One is the SONOS and the other is an nFET pass transistor in series with it. The programming voltages can be found in the device specifications for the SONOS here: https://skywater-pdk--136.org.readthedocs.build/en/136/rules/device-details.html#sonos-cells. I'm still not clear on what the signals are; the original does not have a schematic, and the labels in the layout are somewhat cryptic. I haven't figured out the purpose of having the horizontal LI line through the cell.

@User FYI

should this say 3.8 (not 38)

(1) Yes, it should say 3.8, not 38. (2) That document is only under NDA, and I don't have a copy.

Cool, thanks