Cypress Semiconductor Corp CY7C1564XV18-450BZC

Overview

CY7C1564XV18 from Cypress Semiconductor is a 2M × 36, 72-Mbit QDR® II+ Xtreme SRAM with separate read/write ports, 450 MHz clock support (900 Mbps DDR data rate), 2.5-cycle read latency when DOFF = HIGH, and HSTL I/Os operating at 1.4–1.6 V VDDQ. It delivers concurrent high-bandwidth memory access for network packet buffering in telecom line cards.

For engineers reviewing the CY7C1564XV18 datasheet, CY7C1564XV18 pinout, CY7C1564XV18 application, or CY7C1564XV18 equivalent, key selection criteria include burst depth (2-word), PLL-enabled timing precision, echo clock (CQ/CQ) synchronization, byte write select granularity (BWS[3:0]), and FBGA-165 package compatibility with high-speed PCB layout constraints.

Technical Context

The CY7C1564XV18 implements a synchronous pipelined architecture with independent K (positive) and K (negative) input clocks-both rising edges drive DDR data transfers on dedicated read (Q[35:0]) and write (D[35:0]) ports. Address inputs (A[19:0]) are multiplexed and latched alternately on K/K edges to support 2M × 36 organization.

It integrates a Phase-Locked Loop (PLL) for precise data placement and includes echo clocks (CQ/CQ) aligned to K/K for simplified high-speed capture. The QVLD signal provides edge-aligned valid-data indication, while DOFF enables runtime switching between QDR-II+ (2.5-cycle latency) and QDR-I (1-cycle latency) modes.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 13 mm × 15 mm × 1.4 mm body, 0.8 mm ball pitch, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-bandwidth dual-port SRAM applications.

Compared with IDT72T36120L10BG and IS61WV102436B, the CY7C1564XV18 uniquely delivers 72-Mbit density, 450 MHz DDR throughput, and integrated echo clocks-enabling simpler, higher-performance designs in packet-processing and baseband subsystems.

Availability

CY7C1564XV18 is available at Aetrix Electronics and suitable for telecom infrastructure, 5G radio units, and high-speed packet switching applications requiring stable component supply across extended product lifecycles.

Supply support for CY7C1564XV18 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 and communications markets.

The QDR® II+ Xtreme SRAM product line was designed specifically for deterministic, low-latency, high-throughput memory interfacing in networking and wireless infrastructure-emphasizing concurrent access, timing precision, and signal integrity at multi-Gbps rates.

FAQ

What is the function of the DOFF pin on CY7C1564XV18?

The DOFF pin controls the internal PLL: when pulled HIGH, the device operates in QDR-II+ mode with 2.5-cycle read latency and full 450 MHz capability; when pulled LOW, it reverts to QDR-I timing with 1-cycle latency and reduced maximum frequency (≤167 MHz). This allows runtime mode switching without changing clock sources or controller firmware.

How does the ZQ pin affect signal integrity?

The ZQ pin calibrates the output driver impedance of Q[35:0], CQ, and CQ pins to match the system data bus. Connecting ZQ to a resistor (RQ) to ground sets output impedance to 0.2 × RQ; connecting directly to VDDQ enables minimum impedance mode. Incorrect ZQ termination causes signal reflections and timing violations above 300 MHz.

Can CY7C1564XV18 be used without the PLL enabled?

Yes-asserting DOFF LOW disables the PLL and places the device in QDR-I mode, supporting 1-cycle latency and operation up to 167 MHz. However, echo clocks (CQ/CQ) remain functional but lose PLL-derived phase alignment, requiring external timing compensation for reliable >200 MHz capture.

What is the purpose of BWS[3:0] in write operations?

BWS[3:0] are active-low byte write selects that independently gate four 9-bit segments of the 36-bit D[35:0] bus. When a BWS bit is deasserted, its corresponding byte remains unaltered during the write cycle-enabling partial updates without read-modify-write overhead, critical for metadata patching in packet buffers.