Cypress Semiconductor Corp CY7C1565KV18-450BZC

Overview

CY7C1565KV18-450BZC from Cypress Semiconductor is a 72-Mbit QDR® II+ SRAM with 2M × 36 organization, 450 MHz maximum clock frequency, 2.5-cycle read latency, and separate read/write ports enabling concurrent transactions in high-bandwidth networking and packet buffering systems.

For engineers reviewing the CY7C1565KV18-450BZC datasheet, CY7C1565KV18-450BZC pinout, CY7C1565KV18-450BZC application, or CY7C1565KV18-450BZC equivalent, key selection criteria include DDR interface timing at 900 Mbps effective data rate, HSTL I/O compatibility, echo clock (CQ/CQ) support for precise data capture, and DOFF-controlled latency mode switching between QDR I (1-cycle) and QDR II+ (2.5-cycle) operation.

Technical Context

The device implements a synchronous pipelined architecture with independent read and write ports sharing a multiplexed 19-bit address bus. Each port uses rising edges of complementary K/K clocks for input sampling and output registration, eliminating bus turnaround and supporting full-duplex operation.

It integrates a PLL for accurate data placement and supports programmable output impedance via ZQ calibration. The QVLD signal provides edge-aligned valid-data indication synchronized to CQ/CQ, while BWS[3:0] enables byte-selective writes across four 9-bit segments of the 36-bit data bus.

Key Specifications

Pinout & Package

Package: 165-ball fine-pitch ball grid array (FBGA), 13 mm × 15 mm × 1.4 mm body, RoHS-compliant, with 0.8 mm ball pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar QDR SRAM applications.

Compared with IDT72T3615L10BG and IS61QW25636A-450BQ, CY7C1565KV18-450BZC uniquely combines DOFF-selectable latency, integrated ZQ calibration, and echo clock support - critical for systems requiring dynamic latency adaptation or simplified high-speed data capture without external delay elements.

Availability

CY7C1565KV18-450BZC is available at Aetrix Electronics and suitable for high-speed packet buffering, network switch fabric memory, and telecom line card buffering requiring stable component supply and long-term industrial availability.

Supply support for CY7C1565KV18-450BZC 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) is a fabless semiconductor company specializing in high-performance memory, microcontrollers, and connectivity solutions for industrial, automotive, and communications markets.

CY7C1565KV18 belongs to Cypress's QDR® II+ SRAM product line, engineered specifically for deterministic, low-latency, full-duplex memory access in packet-switched infrastructure where bus turnaround overhead must be eliminated.

FAQ

What is the function of the DOFF pin on CY7C1565KV18-450BZC?

The DOFF pin controls the internal PLL: when asserted HIGH, the device operates in QDR II+ mode with 2.5-cycle read latency; when pulled LOW, it disables the PLL and reverts to QDR I timing with 1-cycle latency and reduced maximum frequency (≤167 MHz). This enables runtime latency tuning without changing clock frequency or firmware.

How does the ZQ pin affect signal integrity?

ZQ connects to an external resistor to ground (typically 240 Ω) to calibrate the output driver impedance of Q[35:0], CQ, and CQ pins to 0.2 × RQ (≈48 Ω), matching standard PCB trace impedances. This minimizes reflections and improves eye diagram margins at 450 MHz clock rates without requiring external series termination.

Can CY7C1565KV18-450BZC support partial writes without read-modify-write cycles?

Yes - the BWS[3:0] inputs enable selective writing of four independent 9-bit segments (D[8:0], D[17:9], D[26:18], D[35:27]) within the 36-bit word. When a BWS bit is deasserted, its corresponding byte remains unaltered, allowing atomic partial updates without reading prior data or using external logic.

What is the role of CQ and CQ echo clocks in system timing?

CQ and CQ are free-running, phase-aligned copies of the K and K input clocks, respectively. They provide a local, jitter-reduced timing reference at the receiver (e.g., FPGA input register), eliminating skew between clock and data paths and relaxing setup/hold timing constraints for Q[35:0] capture at 900 Mbps effective data rate.