CY7C1355B

The CY7C1355B/CY7C1357B is a 3.3V, 256K x 36/ 512K x 18 Synchronous Flow-through Burst SRAM designed specifically to support unlimited true back-to-back Read/Write operations without the insertion of wait states. The CY7C1355B/CY7C1357B is equipped with the advanced No Bus Latency (NoBL) logic required to enable consecutive Read/Write operations with data being transferred on every clock cycle. This feature dramatically improves the throughput of data through the SRAM, especially in systems that require frequent Write-Read transitions.

All synchronous inputs of CY7C1355B/CY7C1357B pass through input registers controlled by the rising edge of the clock. The clock input is qualified by the Clock Enable (CEN) signal, which when deasserted suspends operation and extends the previous clock cycle. Maximum access delay from the clock rise is 6.5 ns (133-MHz device).

Write operations of CY7C1355B/CY7C1357B are controlled by the two or four Byte Write Select (BW_X) and a Write Enable (WE) input. All writes are conducted with on-chip synchronous self-timed write circuitry.

Three synchronous Chip Enables CY7C1355B/CY7C1357B (CE₁, CE₂, CE₃) and an asynchronous Output Enable (OE) provide for easy bank selection and output three-state control. In order to avoid bus contention, the output of CY7C1355B/CY7C1357B drivers are synchronously three-stated during the data portion of a write sequence.