What this part is — and where it fits
The CY7C1473BV33-133AXC is a 72 Mbit synchronous SRAM arranged 4M x 18, built on the NoBL™ architecture. It runs at a 133 MHz clock and delivers a 6.5 ns access time.
133 MHz clock and 6.5 ns access — what they mean for the bus
The 133 MHz clock rate sets the maximum burst throughput at 133 million transfers per second on the parallel interface. The 6.5 ns access time is the window from address assertion to data valid; a controller with a tighter setup/hold budget than 6.5 ns will see data corruption on the bus. This part is synchronous SDR — it uses a single clock edge per transfer, not DDR, so the interface is simpler to route but the peak bandwidth is half that of a DDR SRAM at the same clock. For a design that can tolerate the single-data-rate timing, this part avoids the signal-integrity complexity of DDR termination.