Cypress Semiconductor Corp CY7C1265XV18-633BZXC

Overview

CY7C1265XV18 from Infineon Technologies (formerly Cypress) is a 1 M × 36, 36-Mbit QDR® II+ Xtreme SRAM with four-word burst architecture, 2.5-cycle read latency, and 633 MHz clock operation. It features separate read/write ports, DDR interfaces on both ports (1266 MHz data rate), HSTL I/O, and 1.8 V core / 1.5 V I/O supply. Used in high-bandwidth packet buffering for network switches and routers.

For engineers reviewing the CY7C1265XV18 datasheet, CY7C1265XV18 pinout, CY7C1265XV18 application, or CY7C1265XV18 equivalent, key selection criteria include concurrent read/write capability, echo clock (CQ/CQ) timing support, DOFF-configurable PLL mode, depth expansion via RPS/WPS, and 165-ball FBGA package compatibility with high-speed PCB layout constraints.

Technical Context

The device implements a true dual-port synchronous architecture with independent read and write pipelines, enabling fully concurrent transactions without bus turnaround. Its QDR II+ Xtreme core uses a phase-locked loop (PLL) to align output data with echo clocks CQ and CQ, ensuring precise 1266 MHz DDR capture at system level.

All address and control inputs are registered on rising edges of K and K clocks; data outputs are edge-aligned to CQ/CQ. The DOFF pin selects between 633 MHz QDR II+ mode (PLL enabled, 2.5-cycle latency) and 167 MHz QDR I mode (PLL disabled, 1-cycle latency), providing backward compatibility and flexible timing margining.

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 Pb-free finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C362000B-166BIN and MT47H64M16HR-37E, CY7C1265XV18 delivers deterministic 2.5-cycle latency and true concurrent access-critical for real-time packet switching-while its echo clocks and ZQ calibration simplify high-speed PCB design where signal integrity dominates timing margin.

Availability

CY7C1265XV18 is available at Aetrix Electronics and suitable for network switch fabric design, high-speed test instrumentation, telecom baseband processing, and broadcast video frame buffering requiring stable component supply and long-term lifecycle assurance.

Supply support for CY7C1265XV18 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

Infineon Technologies is a global semiconductor leader headquartered in Munich, Germany, specializing in power management, automotive, industrial, and memory solutions following its acquisition of Cypress Semiconductor.

This device belongs to the QDR® II+ Xtreme SRAM product line, engineered specifically for deterministic, high-bandwidth memory access in networking, test, and telecom infrastructure where bus turnaround elimination and source-synchronous timing are mandatory.

FAQ

What is the function of the DOFF pin on CY7C1265XV18?

The DOFF pin is an active-low PLL disable control. When asserted LOW, it disables the internal phase-locked loop, reverting the device to QDR I timing mode with 1-cycle read latency and a maximum operating frequency of 167 MHz. In normal operation, DOFF must be pulled HIGH via a ≤10 kΩ resistor to enable full QDR II+ performance at 633 MHz.

How does the ZQ pin affect output driver behavior?

The ZQ pin connects to an external 240 Ω resistor to ground to calibrate the output driver impedance to 48 Ω (0.2 × RQ). This ensures optimal signal integrity on matched-impedance PCB traces. Connecting ZQ directly to VDDQ enables minimum output impedance mode; leaving it unconnected or tied to GND violates specifications and may cause undefined behavior.

Can CY7C1265XV18 perform simultaneous read and write operations to the same memory location?

No. While the device supports fully concurrent read and write operations to *different* addresses, writing to an address currently being read from results in undefined data on the Q[35:0] bus. The architecture guarantees coherency only for independent address accesses; overlapping address conflicts require external arbitration in system design.

What is the role of the QVLD signal in system timing?

QVLD is a synchronous output strobe edge-aligned to CQ and CQ, asserting one clock cycle before valid read data appears on Q[35:0]. It serves as a hardware-ready signal for downstream logic (e.g., FPGA capture registers), eliminating the need for fixed delay chains or dynamic deskew circuits when latching high-speed DDR outputs.