Infineon Technologies CY7C1265KV18-450BZXC

Overview

CY7C1265KV18 from Cypress Semiconductor is a 1M × 36, 36-Mbit QDR® II+ SRAM with 2.5-cycle read latency, 450 MHz clock operation (900 MT/s effective data rate), 1.8 V core supply, and 1.4–1.8 V I/O supply. It features separate read/write ports, DDR interfaces on both ports, echo clocks (CQ/CQ), and QVLD data-valid signaling - deployed in high-bandwidth packet buffering for network line cards and telecom switching fabric.

For engineers reviewing the CY7C1265KV18 datasheet, CY7C1265KV18 pinout, CY7C1265KV18 application, or CY7C1265KV18 equivalent, key selection criteria include burst depth (four 36-bit words), DOFF-controlled latency mode (QDR I vs. QDR II+), byte write select granularity (BWS[3:0]), HSTL I/O compliance, and 165-ball FBGA (13 × 15 × 1.4 mm) package compatibility with high-speed PCB layout constraints.

Technical Context

This device implements a synchronous pipelined architecture with independent read and write ports sharing a multiplexed address bus. Address latching occurs on alternating rising edges of K and K clocks, enabling concurrent access without bus turnaround. The internal PLL ensures precise data placement aligned to echo clocks CQ and CQ.

Read operations deliver four sequential 36-bit words per access with 2.5-cycle latency when DOFF = HIGH; write operations are self-timed and support byte-level granularity via BWS[3:0]. All I/O uses HSTL Class I inputs and variable-drive HSTL outputs, with ZQ-pin impedance calibration supporting 0.2×RQ output tuning.

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 QDR II+ SRAM applications.

Compared with CY7C1265KV18-400BZXC, the -450BZXC offers 12.5% higher bandwidth and tighter timing margins; versus AS7C361024A-166BIN, it provides true dual-port DDR operation, deterministic latency, and system-level signal integrity features essential for modern high-speed interconnects.

Availability

CY7C1265KV18-450BZXC is available at Aetrix Electronics and suitable for packet buffering in 10G/25G line cards, high-speed switch fabric memory, and baseband processing in 4G/LTE eNodeB requiring stable component supply across extended production lifecycles.

Supply support for CY7C1265KV18-450BZXC 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 memory, microcontrollers, and connectivity solutions for industrial, automotive, and communications markets.

The QDR® II+ SRAM product line was designed specifically for high-throughput, low-latency networking and telecommunications infrastructure - emphasizing deterministic timing, concurrent access, and signal integrity at multi-GHz data rates.

FAQ

What is the function of the DOFF pin on CY7C1265KV18-450BZXC?

The DOFF (PLL Disable) pin controls the internal phase-locked loop. When pulled HIGH, the PLL is active and the device operates in QDR II+ mode with 2.5-cycle read latency at up to 450 MHz. When pulled LOW, the PLL is disabled and the device reverts to QDR I timing with 1-cycle latency and a maximum frequency of 167 MHz. This pin must be externally biased - typically with a 10 kΩ pull-up resistor for normal operation.

How does the ZQ pin affect output drive strength?

The ZQ pin connects to an external resistor (RQ) tied to ground to calibrate the output impedance of Q[35:0], CQ, and CQ pins to 0.2 × RQ. For example, a 240 Ω resistor sets output impedance to 48 Ω, matching standard 50 Ω PCB traces. If ZQ is tied directly to VDDQ, the device enters minimum-impedance mode (≈25 Ω). ZQ must never be left floating or connected to ground, as this disables calibration and risks signal integrity failure.

Can CY7C1265KV18-450BZXC perform partial writes without corrupting adjacent data?

Yes. The device supports byte-level write masking using BWS[3:0], each controlling a 9-bit segment of the 36-bit data bus. When a BWS signal is HIGH, the corresponding 9-bit byte is ignored during the write cycle, leaving stored data unchanged. This enables safe partial updates - for example, modifying only header fields in a packet buffer while preserving payload contents - without requiring read-modify-write sequences.

What is the role of QVLD in system timing design?

QVLD is a source-synchronous, edge-aligned indicator that asserts precisely when Q[35:0] carries valid data - synchronized to the rising edges of CQ and CQ. Unlike asynchronous ready signals, QVLD eliminates setup/hold uncertainty at the receiver, allowing FPGA or ASIC logic to sample Q[35:0] on the same clock edge that drives QVLD. This simplifies timing closure in >500 Mbps DDR links and removes the need for dynamic deskew logic.