25 ns dual-port SRAM — what this chip does
The Cypress CY7C028V-25AC is a 1 Mbit dual-port asynchronous SRAM organized as 64K x 16. It gives two independent systems — or two processor cores — simultaneous read/write access to the same memory array through separate address, data, and control buses. The 25 ns access time means each port can complete a read or write cycle in 25 ns, which sets the bus timing budget for the interface logic. This part is typically used in shared-memory buffers, mailbox registers, or data-exchange blocks in telecom line cards, industrial controllers, and multiprocessor systems where a common scratchpad is needed without arbitration overhead.
3.3 V supply — compatibility confirmed
No level translation is needed on the I/O if the host controller also operates at 3.3 V. The 25 ns write cycle time (word and page modes) matches the read access time, so back-to-back operations at the same port run at the same speed.
Housed in a 100-TQFP (14x14 mm) package, surface-mount only. For extended-temperature or automotive applications, a different grade would be needed.
This part is listed as obsolete by the manufacturer. For new designs, a pin-compatible dual-port SRAM from the same Cypress family (such as a CY7C028V variant with a different speed grade or a later-generation part) should be evaluated.