The Infineon CY7C006A-20AC is a 128Kbit dual-port asynchronous SRAM organized as 16K words by 8 bits. Its defining feature is two independent ports with separate address, data, and control lines, allowing two bus masters (two CPUs, a CPU and a DSP, or a CPU and an FPGA) to read or write the same memory array simultaneously. The 20 ns access time means the part can keep up with fast 5V logic without wait states in most mid-speed systems.
The 20 ns access time and matching 20 ns write cycle time mean the memory can complete a read or write in one clock cycle on a 50 MHz bus, or in two cycles on a 100 MHz bus. For a dual-port part this matters because arbitration logic (busy/flag signals) adds a few nanoseconds; the 20 ns window gives you margin to resolve contention without missing the next cycle. If your system runs faster than 50 MHz or uses a 3.3V memory interface, this part is not the right fit — you would need a faster or lower-voltage dual-port SRAM.
If your application sees temperature swings outside 0°C to 70°C, look for an industrial-temperature dual-port SRAM in the same Cypress/Infineon family.
The CY7C006A-20AC is officially obsolete. Infineon (formerly Cypress) no longer manufactures this part. There is no direct pin-compatible drop-in replacement listed in the official records. If you are designing a new board, do not use this part; select a current-production dual-port SRAM or a modern alternative.