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CY7C2268XV18 Datasheet, PDF (1/29 Pages) Cypress Semiconductor – 36-Mbit DDR II+ Xtreme SRAM Two-Word Burst Architecture (2.5 Cycle Read Latency) with ODT
CY7C2268XV18, CY7C2270XV18
36-Mbit DDR II+ Xtreme SRAM Two-Word
Burst Architecture (2.5 Cycle Read Latency) with ODT
36-Mbit DDR II+ Xtreme SRAM Two-Word Burst Architecture (2.5 Cycle Read Latency) with ODT
Features
■ 36-Mbit density (2 M × 18, 1 M × 36)
■ 633 MHz clock for high bandwidth
■ Two-word burst for reducing address bus frequency
■ Double data rate (DDR) interfaces (data transferred at
1266 MHz) at 633 MHz
■ Available in 2.5 clock cycle latency
■ Two input clocks (K and K) for precise DDR timing
❐ SRAM uses rising edges only
■ Echo Clocks (CQ and CQ) simplify data capture in high speed
systems
■ Data valid pin (QVLD) to indicate valid data on the output
■ On-die termination (ODT) feature
❐ Supported for DQ[x:0], BWS[x:0], and K/K inputs
■ Synchronous internally self-timed writes
■ DDR II+ Xtreme operates with 2.5 cycle read latency when
DOFF is asserted HIGH
■ Operates similar to DDR I Device with 1 cycle read latency
when DOFF is asserted LOW
■ Core VDD = 1.8 V ± 0.1 V; I/O VDDQ = 1.4 V to 1.6 V
❐ Supports 1.5 V I/O supply
■ HSTL inputs and variable drive HSTL output buffers
■ Available in 165-ball FBGA package (13 × 15 × 1.4 mm)
■ Offered in Pb-free packages
■ JTAG 1149.1 compatible test access port
■ Phase-locked loop (PLL) for accurate data placement
Configurations
With Read Cycle Latency of 2.5 cycles:
CY7C2268XV18 – 2 M × 18
CY7C2270XV18 – 1 M × 36
Functional Description
The CY7C2268XV18, and CY7C2270XV18 are 1.8 V
Synchronous Pipelined SRAMs equipped with DDR II+
architecture. The DDR II+ consists of an SRAM core with
advanced synchronous peripheral circuitry. 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 K and K. Each
address location is associated with two 18-bit words
(CY7C2268XV18), or 36-bit words (CY7C2270XV18) that burst
sequentially into or out of the device.
These devices have an On-Die Termination feature supported
for DQ[x:0], BWS[x:0], and K/K inputs, which helps eliminate
external termination resistors, reduce cost, reduce board area,
and simplify board routing.
Asynchronous inputs include an output impedance matching
input (ZQ). Synchronous data outputs (Q, sharing the same
physical pins as the data inputs D) are tightly matched to the two
output echo clocks CQ/CQ, eliminating the need for separately
capturing data from each individual DDR SRAM in the system
design.
All synchronous inputs pass through input registers controlled by
the K or K input clocks. All data outputs pass through output
registers controlled by the K or K input clocks. Writes are
conducted with on-chip synchronous self-timed write circuitry.
Selection Guide
Maximum Operating Frequency
Maximum Operating Current
Description
633 MHz 600 MHz Unit
633
600
MHz
× 18
965
910
mA
× 36 1230
1165
Cypress Semiconductor Corporation • 198 Champion Court
Document Number: 001-70332 Rev. *B
• San Jose, CA 95134-1709 • 408-943-2600
Revised October 25, 2012