Cypress Semiconductor Corp CY7C1570XV18-633BZXC

Overview

CY7C1570XV18-633BZXC from Cypress Semiconductor is a 72-Mbit (2M × 36) synchronous pipelined DDR II+ Xtreme SRAM with 2.5-cycle read latency, 633 MHz clock operation, and HSTL I/O interface. It delivers 1266 MT/s data throughput via double-data-rate transfers on rising edges of complementary K/K clocks, and integrates echo clocks (CQ/CQ) and QVLD for precise high-speed data capture in networking and test equipment memory buffers.

For engineers reviewing the CY7C1570XV18-633BZXC datasheet, CY7C1570XV18-633BZXC pinout, CY7C1570XV18-633BZXC application, or CY7C1570XV18-633BZXC equivalent, key selection criteria include its 2M × 36 organization, 1.8 V core / 1.4–1.6 V I/O supply, JTAG 1149.1 compliance, and PLL-enabled timing alignment for deterministic DDR II+ burst reads.

Technical Context

This SRAM implements a two-word burst architecture where each address access retrieves two consecutive 36-bit words on alternating K/K rising edges. Its internal PLL synchronizes echo clocks CQ/CQ to K, enabling source-synchronous data capture without board-level skew compensation.

All synchronous inputs (A, R/W, LD, BWS[3:0]) are registered on K's rising edge; write data is latched on both K and K edges; read data is driven on both K and K edges with QVLD edge-aligned to CQ/CQ. DOFF pin selects between 2.5-cycle DDR II+ mode (DOFF = HIGH) and 1-cycle DDR I mode (DOFF = LOW).

Key Specifications

Pinout & Package

Package: 165-ball fine-pitch ball grid array (FBGA), 13 mm × 15 mm × 1.4 mm body, RoHS-compliant Pb-free construction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed synchronous SRAM applications.

Compared with AS7C362000B-166BCN and IS61WV204836BLL-15BLI, CY7C1570XV18-633BZXC delivers 7.6× higher effective bandwidth (1266 vs ≤166 MT/s) and eliminates board-level timing closure challenges via integrated echo clocks and QVLD - making it uniquely suited for deterministic high-speed packet and waveform memory.

Availability

CY7C1570XV18-633BZXC is available at Aetrix Electronics and suitable for high-speed packet buffering, test equipment waveform memory, and FPGA co-processor cache applications requiring stable component supply and long-term industrial availability.

Supply support for CY7C1570XV18-633BZXC includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Cypress Semiconductor (now part of Infineon Technologies) designs high-performance memory and programmable solutions for demanding embedded and communications systems.

The DDR II+ Xtreme SRAM product line targets applications needing deterministic low-latency, high-throughput memory interfaces - especially in networking infrastructure, automated test equipment, and real-time signal processing where source-synchronous timing eliminates system-level skew.

FAQ

What is the function of the DOFF pin on CY7C1570XV18-633BZXC?

The DOFF pin is an active-LOW PLL disable control. When pulled HIGH (typically via 10 kΩ pull-up), the internal PLL is enabled, supporting 2.5-cycle read latency and full 633 MHz DDR II+ operation. When tied LOW, the PLL is disabled and the device operates in DDR I mode with 1-cycle latency and reduced maximum frequency (≤167 MHz), providing backward compatibility with legacy timing controllers.

How does the ZQ pin affect output drive strength?

The ZQ pin connects to an external 240 Ω resistor to ground, enabling on-die calibration of DQ and CQ output driver impedance to 48 Ω (0.2 × RQ). This matches standard HSTL-15 transmission lines, minimizing reflections and improving signal integrity. If ZQ is tied directly to VDDQ, the device enters minimum-impedance mode (~30 Ω); it must never be left floating or connected to GND.

Can CY7C1570XV18-633BZXC operate with only a single-ended clock?

No. The device requires true differential K and K clock inputs. Both signals must be driven with complementary CMOS or HSTL waveforms meeting specified voltage thresholds and skew limits. Using only K while leaving K unconnected violates AC timing specifications and will cause functional failure - the K input is not optional and is actively used for data capture and output timing.

What is the purpose of the QVLD signal in system design?

QVLD is an edge-aligned valid-data indicator that asserts HIGH precisely when DQ[35:0] contains stable, correctly timed read data - synchronized to the rising edges of CQ and CQ. It replaces the need for complex strobe-window detection logic in receiving FPGAs or ASICs, allowing direct use of QVLD as a latch-enable signal to capture clean data with minimal setup/hold margin.