CY7C1523KV18_13 Datasheet, PDF (1/28 Pages) Cypress Semiconductor – 72-Mbit DDR II SIO SRAM Two-Word Burst Architecture

CY7C1523KV18
72-Mbit DDR II SIO SRAM Two-Word
Burst Architecture
72-Mbit DDR II SIO SRAM Two-Word Burst Architecture
Features
■ 72-Mbit density (4 M × 18)
■ 250 MHz clock for high bandwidth
■ Two-word burst for reducing address bus frequency
■ Double data rate (DDR) interfaces (data transferred at
500 MHz) at 250 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 1 cycle read latency when
DOFF is asserted LOW
■ 1.8 V core power supply with HSTL inputs and outputs
■ Variable drive HSTL output buffers
■ Expanded HSTL output voltage (1.4 V–V_DD)
❐ Supports both 1.5 V and 1.8 V I/O supply
■ Available in 165-ball fine pitch ball grid array (FBGA) package
(13 × 15 × 1.4 mm)
■ Offered in both Pb-free package
■ JTAG 1149.1 compatible test access port
■ Phase-locked loop (PLL) for accurate data placement
Configurations
CY7C1523KV18 – 4 M × 18
Functional Description
The CY7C1523KV18 is a1.8 V Synchronous Pipelined SRAMs,
equipped with DDR II SIO (Double Data Rate Separate I/O)
architecture. The DDR II SIO consists of two separate ports: the
read port and the write port to access the memory array. The
read port has data outputs to support read operations and the
write port has data inputs to support write operations. The DDR
II SIO has separate data inputs and data outputs to completely
eliminate the need to “turnaround” the data bus required with
common I/O devices. Access to each port is accomplished
through a common address bus. 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 18-bit words in the case of
CY7C1523KV18 that burst sequentially into or out of the device.
Asynchronous inputs include an output impedance matching
input (ZQ). Synchronous data outputs are tightly matched to the
two output echo clocks CQ/CQ, eliminating the need to capture
data separately from each individual DDR II SIO 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
Maximum Operating Frequency
Maximum Operating Current
Description
250 MHz Unit
250
MHz
× 18
430
mA
Cypress Semiconductor Corporation • 198 Champion Court
Document Number: 001-00438 Rev. *L
• San Jose, CA 95134-1709 • 408-943-2600
Revised March 28, 2013