Infineon Technologies CY7C1265V18-400BZXC

Overview

CY7C1265V18 from Cypress Semiconductor is a 1M × 36-bit, 36-Mbit QDR-II+ SRAM with 4-word burst architecture, 2.5-cycle read latency, and dual DDR interfaces operating at 400 MHz (800 MT/s effective data rate). It features separate read/write ports, HSTL I/O, 1.8V core supply, and 1.4–1.8V I/O supply, deployed in high-bandwidth packet buffering for network switches and routers.

For engineers reviewing the CY7C1265V18 datasheet, CY7C1265V18 pinout, CY7C1265V18 application, or CY7C1265V18 equivalent, key selection criteria include burst depth, port independence, DLL-controlled timing alignment, echo clock (CQ/CQ) support for source-synchronous capture, and FBGA-165 package compatibility with high-speed PCB layout constraints.

Technical Context

The CY7C1265V18 implements a true dual-port synchronous architecture with physically independent read and write data paths-no bus turnaround required. Its QDR-II+ core uses a Delay Lock Loop (DLL) to align CQ/CQ echo clocks precisely with K/K input edges, enabling reliable 800 MT/s DDR capture at 400 MHz.

All address, control, and data signals are registered on rising edges of K (positive) and K (negative) clocks. The device supports depth expansion via four byte write selects (BWS[3:0]) and independent port enables (RPS/WPS), with full coherency ensuring the most recent write is always available on subsequent reads.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 15 mm × 17 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 burst SRAM applications.

Compared with IDT72T36150 and IS61WV102436B, the CY7C1265V18 uniquely delivers 400 MHz operation with DLL-aligned echo clocks and ZQ-calibrated outputs-enabling robust 800 MT/s signaling in dense, high-speed PCB layouts where timing closure is critical.

Availability

CY7C1265V18 is available at Aetrix Electronics and suitable for network infrastructure, test instrumentation, telecom baseband, and FPGA acceleration applications requiring stable component supply and long-term obsolescence management.

Supply support for CY7C1265V18 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 QDR-II+ SRAM product line targets applications needing deterministic, high-bandwidth, low-latency memory access-specifically developed for packet buffering, protocol acceleration, and real-time signal processing in networking and test equipment.

FAQ

What is the function of the ZQ pin on CY7C1265V18?

The ZQ pin calibrates output driver impedance for CQ, CQ, and Q[35:0] signals. It must be connected to a 240 Ω resistor to ground to set output impedance to 48 Ω (0.2 × RQ), or tied to VDDQ for minimum impedance mode. Floating or grounding ZQ violates specification and causes timing violations.

Can CY7C1265V18 operate without the DLL enabled?

Yes-asserting DOFF (low) disables the DLL, reverting the device to QDR-I timing mode with maximum 167 MHz operation. In this mode, CQ/CQ become simple buffered copies of K/K, and read latency increases to 3 cycles. Full QDR-II+ performance requires DOFF high (pulled up via ≤10 kΩ).

How does the 4-word burst work with 1M × 36 organization?

Each read or write access transfers four consecutive 36-bit words starting from the addressed location. Internally, the 256K × 36 array is accessed using 18 address bits (A[17:0]); the burst sequence increments the lower two bits automatically, delivering Q[35:0] on four successive K/K edges within 2.5 clock cycles.

Is CY7C1265V18 pin-compatible with other devices in the CY7C126xV18 family?

No-while all share the 165-ball FBGA package, pin assignments differ significantly across x8/x9/x18/x36 variants due to varying data bus widths and write select configurations. CY7C1265V18 uses BWS[3:0] and D[35:0]/Q[35:0], whereas CY7C1261V18 uses NWS[1:0] and D[7:0]/Q[7:0]; direct substitution is not possible without PCB redesign.