Functional Description
The CY7C1618KV18, and CY7C1620KV18 are 1.8-V synchronous pipelined SRAM equipped with DDR II architecture. The DDR II consists of an SRAM core with advanced synchronous peripheral circuitry and a 1-bit burst counter. Addresses for read and write are latched on alternate rising edges of the input (K) clock. Write data is registered on the rising edges of both K and K. Read data is driven on the rising edges of C and C if provided, or on the rising edge of K and K if C/C are not provided. On CY7C1618KV18 and CY7C1620KV18, the burst counter takes in the least significant bit of the external address and bursts two 18-bit words in the case of CY7C1618KV18 and two 36-bit words in the case of CY7C1620KV18 sequentially into or out of the device.
FEATUREs
■ 144-Mbit density (8M × 18, 4M × 36)
■ 333 MHz clock for high bandwidth
■ Two-word burst for reducing address bus frequency
■ Double data rate (DDR) interfaces (data transferred at 666 MHz) at 333 MHz
■ Two input clocks (K and K) for precise DDR timing
❐ SRAM uses rising edges only
■ Two input clocks for output data (C and C) to minimize clock skew and flight time mismatches
■ Echo clocks (CQ and CQ) simplify data capture in high-speed systems
■ Synchronous internally self-timed writes
■ DDR II operates with 1.5-cycle read latency when DOFF is asserted high
■ Operates similar to DDR I device with one cycle read latency when DOFF is asserted low
■ 1.8-V core power supply with high-speed transceiver logic (HSTL) inputs and outputs
■ Variable drive HSTL output buffers
■ Expanded HSTL output voltage (1.4 V–VDD)
❐ Supports both 1.5-V and 1.8-V I/O supply
■ Available in 165-ball fine-pitch ball grid array (FBGA) package (15 × 17 × 1.4 mm)
■ Offered in Pb-free packages
■ JTAG 1149.1 compatible test access port
■ Phase locked loop (PLL) for accurate data placement