Inside the stacked RAM modules used in the Apple III
DigiDelay SRAMs – Electric Druid
Serial SRAM - Microchip Technology | Mouser
Microchip - Serial SRAM Memory Family - RUTRONIK-TEC
50 PCS FM24C04B-G SOP-8 FM24C04 24C04 4Kb Serial 5V F-RAM Memory Chip IC | eBay
Serial SRAM and Serial NVSRAM | Microchip Technology
Does anyone know anything about this AST Advantage Premium card? It seems to be a RAM expansion with a serial and parallel port, but it looks like it's missing a chip :