Functional Description
The CY7C451, CY7C453, and CY7C454 are high-speed, low-power, first-in first-out (FIFO) memories with clocked read and write interfaces. Both FIFOs are 9 bits wide. The CY7C451 has a 512-word by 9-bit memory array, the CY7C453 has a 2048-word by 9-bit memory array, and the CY7C454 has a 4096-word by 9-bit memory array. Devices can be cascaded to increase FIFO depth. Programmable features include Almost Full/Empty flags and generation/checking of parity. These FIFOs provide solutions for a wide variety of data buffering needs, including high-speed data acquisition, multiprocessor interfaces, and communications buffering.

Features
• High-speed, low-power, first-in first-out (FIFO) memories
• 512 x 9 (CY7C451)
• 2,048 x 9 (CY7C453)
• 4,096 x 9 (CY7C454)
• 0.65 micron CMOS for optimum speed/power
• High-speed 83-MHz operation (12 ns read/write cycle time)
• Low power — ICC=70 mA
• Fully asynchronous and simultaneous read and write operation
• Empty, Full, Half Full, and programmable Almost Empty and Almost Full status flags
• TTL compatible
• Retransmit function
• Parity generation/checking
• Output Enable (OE) pins
• Independent read and write enable pins
• Center power and ground pins for reduced noise
• Supports free-running 50% duty cycle clock inputs
• Width Expansion Capability
• Depth Expansion Capability
• Available in PLCC packages