8Kbit dual-port asynchronous SRAM — shared-memory workhorse
The Infineon CY7C131-55JXC is an 8Kbit (organized as 1K x 8) dual-port asynchronous SRAM. The 55 ns access time sets the bus timing budget.
55 ns access — timing closure for the shared bus
The 55 ns access time and 55 ns write cycle time set the bus timing budget.
This means Infineon no longer produces it, and no last-time-buy window remains. The only supply channel is the surplus and independent distribution market, where sealed factory reels and tube stock from end-of-life buyouts still circulate. No direct factory replacement is listed; the closest functional alternative would be a pin-compatible dual-port SRAM (e.g., CY7C131-55JI, which shares the same 52-PLCC footprint and 55 ns timing but may differ in lead finish or temperature range — confirm compatibility before substituting).
52-PLCC package — footprint and rework notes
The 52-lead PLCC with J-leads is a legacy surface-mount package. The supplier device package dimension is 19.13 x 19.13 mm, which sets the land pattern and keep-out zone on the PCB.