18-Mbit DDR-II SRAM 4-WordBurst Architecture

CY7C1317CV18, CY7C1917CV18

CY7C1319CV18, CY7C1321CV18

CypressSemiconductor Corporation 198 Champion Court San Jose,CA 95134-1709 408-943-2600
Document Number: 001-07161 Rev. *D Revised June 18, 2008

Features

18-Mbit density (2M x 8, 2M x 9, 1M x 18, 512K x 36)
300 MHz clock for high bandwidth
4-word burst for reducing address bus frequency
Double Data Rate (DDR) interfaces
(data transferred at 600 MHz) at 300 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 the DLL is
enabled
Operates similar to a DDR-I device with 1 cycle read latency in
DLL off mode
1.8V core power supply with HSTL inputs and outputs
Variable drive HSTL output buffers
Expanded HSTL output voltage (1.4V–VDD)
Available in 165-Ball FBGA package (13 x 15 x 1.4 mm)
Offered in both Pb-free and non Pb-free packages
JTAG 1149.1 compatible test access port
Delay Lock Loop (DLL) for accurate data placement

Configurations

CY7C1317CV18 – 2M x 8
CY7C1917CV18 – 2M x 9
CY7C1319CV18 – 1M x 18
CY7C1321CV18 – 512K x 36

Functional Description

The CY7C1317CV18, CY7C1917CV18, CY7C1319CV18, and
CY7C1321CV18 are 1.8V Synchronous Pipelined SRAMs
equipped with DDR-II architecture. The DDR-II consists of an
SRAM core with advanced synchronous peripheral circuitry and
a two-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. Each address location
is associated with four 8-bit words in the case of CY7C1317CV18
and four 9-bit words in the case of CY7C1917CV18 that burst
sequentially into or out of the device. The burst counter always
starts with a ‘00’ internally in the case of CY7C1317CV18 and
CY7C1917CV18. For CY7C1319CV18 and CY7C1321CV18,
the burst counter takes in the least two significant bits of the
external address and bursts four 18-bit words in the case of
CY7C1319CV18, and four 36-bit words in the case of
CY7C1321CV18, sequentially into or out of the device.
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 to capture data
separately from each individual DDR SRAM in the system
design. Output data clocks (C/C) enable maximum system
clocking and data synchronization flexibility.
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 C or C (or K or K in a single clock
domain) input clocks. Writes are conducted with on-chip
synchronous self-timed write circuitry.

Selection Guide

Description 300 MHz 278 MHz 250 MHz 200 MHz 167 MHz Unit
Maximum Operating Frequency 300 278 250 200 167 MHz
Maximum Operating Current x8 770 720 670 580 515 mA
x9 770 720 670 580 515
x18 810 760 700 600 540
x36 890 830 765 655 600
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