Cypress CY7C1546V18 manual Features, Functional Description, Configurations, Selection Guide

CY7C1546V18, CY7C1557V18

CY7C1548V18, CY7C1550V18

72-Mbit DDR-II+ SRAM 2-Word Burst Architecture (2.0 Cycle Read Latency)

Features

■72-Mbit density (8M x 8, 8M x 9, 4M x 18, 2M x 36)

■375 MHz clock for high bandwidth

■2-word burst for reducing address bus frequency

■Double Data Rate (DDR) interfaces

(data transferred at 750 MHz) at 375 MHz

■Available in 2.0 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

■Synchronous internally self-timed writes

■Core VDD = 1.8V ± 0.1V; IO VDDQ = 1.4V to VDD [1]

■HSTL inputs and variable drive HSTL output buffers

■Available in 165-Ball FBGA package (15 x 17 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

Functional Description

The CY7C1546V18, CY7C1557V18, CY7C1548V18, and CY7C1550V18 are 1.8V Synchronous Pipelined SRAM 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 both K and K. Each address location is associated with two 8-bit words (CY7C1546V18), 9-bit words (CY7C1557V18), 18-bit words (CY7C1548V18), or 36-bit words (CY7C1550V18) that burst 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 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.

Configurations

With Read Cycle Latency of 2.0 cycles:

CY7C1546V18 – 8M x 8

CY7C1557V18 – 8M x 9

CY7C1548V18 – 4M x 18

CY7C1550V18 – 2M x 36

Selection Guide

Description		375 MHz	333 MHz	300 MHz	Unit
Maximum Operating Frequency		375	333	300	MHz
Maximum Operating Current	x8	1300	1200	1100	mA
	x9	1300	1200	1100
	x18	1300	1200	1100
	x36	1300	1200	1100

Note

1.The QDR consortium specification for VDDQ is 1.5V + 0.1V. The Cypress QDR devices exceed the QDR consortium specification and are capable of supporting VDDQ = 1.4V to VDD.

Cypress Semiconductor Corporation • 198 Champion Court	•	San Jose, CA 95134-1709	•	408-943-2600
Document Number: 001-06550 Rev. *E		Revised March 11, 2008

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