What the 55 ns access time means for your bus timing
The CY7C136-55NXC: In a shared-memory system where two processors or a processor and an FPGA arbitrate for the same address space, the 55 ns window sets the minimum cycle time for read/write operations — the bus master must hold address and control valid for at least that long before the data is guaranteed on the bus.
The part is no longer supported for new designs and has no factory last-time-buy window remaining. Each lot is verified for date-code consistency, marking integrity, and package condition before shipment — the 52-PQFP (10x10 mm) footprint is visually inspected for bent leads or mold-compound damage that could indicate rework or mishandling.
The part ships in a 52-BQFP (bumpered quad flat pack) with a 10x10 mm body. The surface-mount footprint uses a fine-pitch gull-wing lead form — the 0.65 mm typical lead pitch requires a solder-paste stencil with aperture reduction to avoid bridging during reflow.