CY7C2561KV18, CY7C2576KV18
CY7C2563KV18, CY7C2565KV18
PRELIMINARY
72-Mbit QDR™-II+ SRAM 4-Word Burst
Architecture (2.5 Cycle Read Latency) with ODT
Features
Configurations
■ Separate independent read and write data ports
❐ Supports concurrent transactions
With Read Cycle Latency of 2.5 cycles:
CY7C2561KV18 – 8M x 8
■ 550 MHz clock for high bandwidth
CY7C2576KV18 – 8M x 9
CY7C2563KV18 – 4M x 18
CY7C2565KV18 – 2M x 36
■ 4-word burst for reducing address bus frequency
■ Double Data Rate (DDR) interfaces on both read and write
ports (data transferred at 1100 MHz) at 550 MHz
Functional Description
■ Available in 2.5 clock cycle latency
The CY7C2561KV18, CY7C2576KV18, CY7C2563KV18, and
CY7C2565KV18 are 1.8V Synchronous Pipelined SRAMs,
equipped with QDR-II+ architecture. Similar to QDR-II archi-
tecture, QDR-II+ architecture consists of two separate ports: the
read port and the write port to access the memory array. The
read port has dedicated data outputs to support read operations
and the write port has dedicated data inputs to support write
operations. QDR-II+ architecture has separate data inputs and
data outputs to completely eliminate the need to “turn-around”
the data bus that exists with common IO devices. Each port is
accessed through a common address bus. Addresses for read
and write addresses are latched on alternate rising edges of the
input (K) clock. Accesses to the QDR-II+ read and write ports are
completely independent of one another. To maximize data
throughput, both read and write ports are equipped with DDR
interfaces. Each address location is associated with four 8-bit
words (CY7C2561KV18), 9-bit words (CY7C2576KV18), 18-bit
words (CY7C2563KV18), or 36-bit words (CY7C2565KV18) that
burst sequentially into or out of the device. Because data is trans-
ferred into and out of the device on every rising edge of both input
clocks (K and K), memory bandwidth is maximized while simpli-
fying system design by eliminating bus “turn-arounds”.
■ 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 D
, BWS
, and K/K inputs
[x:0]
[x:0]
■ Single multiplexed address input bus latches address inputs
for read and write ports
■ Separate port selects for depth expansion
■ Synchronous internally self-timed writes
■ QDR™-II+ operates with 2.5 cycle read latency when DOFF is
asserted HIGH
■ Operates similar to QDR-I device with 1 cycle read latency
when DOFF is asserted LOW
■ Available in x8, x9, x18, and x36 configurations
These devices have an On-Die Termination feature supported
■ Full data coherency, providing most current data
for D
, BWS
, and K/K inputs, which helps eliminate
[x:0]
[x:0]
■ Core V = 1.8V± 0.1V; IO V
= 1.4V to V
DD
external termination resistors, reduce cost, reduce board area,
and simplify board routing.
DD
DDQ
❐ Supports both 1.5V and 1.8V IO supply
Depth expansion is accomplished with port selects, which
enables each port to operate independently.
■ HSTL inputs and variable drive HSTL output buffers
■ 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
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.
■ Phase Locked Loop (PLL) for accurate data placement
Table 1. Selection Guide
Description
550 MHz
550
500 MHz
500
450 MHz
450
400 MHz
400
Unit
MHz
mA
Maximum Operating Frequency
Maximum Operating Current
x8
x9
900
830
760
690
900
830
760
690
x18
x36
920
850
780
710
1310
1210
1100
1000
Note
1. The Cypress QDR-II+ devices surpass the QDR consortium specification and can support V
= 1.4V to V
.
DD
DDQ
Cypress Semiconductor Corporation
Document Number: 001-15887 Rev. *E
•
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised April 24, 2009
