Infineon Technologies CY7C25682KV18-400BZC

Overview

CY7C25682KV18 from Cypress Semiconductor is a 72-Mbit (4M × 18) synchronous pipelined DDR II+ SRAM with two-word burst architecture, 2.5-cycle read latency (DOFF = HIGH), 550 MHz clock operation, and on-die termination (ODT) for D[x:0], BWS[x:0], and K/K inputs. It delivers 1100 MT/s data throughput via double-data-rate I/O and supports 1.8 V core / 1.4–1.8 V I/O supply in high-bandwidth networking and packet buffering applications.

For engineers reviewing the CY7C25682KV18 datasheet, CY7C25682KV18 pinout, CY7C25682KV18 application, or CY7C25682KV18 equivalent, key selection criteria include DDR II+ timing compliance, echo clock (CQ/CQ) synchronization for clean data capture, QVLD validity signaling, HSTL-compatible I/O drive, and FBGA-165 package compatibility with high-density memory subsystems.

Technical Context

This device implements a synchronous pipelined SRAM core with DDR II+ interface logic, using dual input clocks (K and K) - both rising edges register write data and drive read data. Address latching occurs on alternating K edges, enabling continuous burst access without address bus toggling between words.

The integrated PLL ensures precise data placement relative to echo clocks (CQ/CQ), while ODT eliminates external termination resistors for DQ, BWS, and clock inputs. The DOFF pin selects between 2.5-cycle (DDR II+) and 1-cycle (DDR I-compatible) read latency modes, allowing system-level timing flexibility.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed burst SRAM applications.

Compared with AS7C36256PFS-15BIN and IS61WV102418BLL-10TLI, CY7C25682KV18 uniquely delivers DDR II+ burst timing, on-die termination, and echo clocks - critical for deterministic, high-bandwidth memory subsystems in networking and telecom infrastructure where signal integrity and timing predictability are non-negotiable.

Availability

CY7C25682KV18 is available at Aetrix Electronics and suitable for high-speed packet buffering, network switch ASIC interfacing, telecom baseband processing, and industrial real-time control buffering requiring stable component supply and long-term lifecycle support.

Supply support for CY7C25682KV18 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.

CY7C25682KV18 belongs to Cypress's QDR/DDR II+ SRAM product line, designed specifically for ultra-low-latency, high-bandwidth memory subsystems in networking equipment, base stations, and high-end test instrumentation.

FAQ

What is the function of the DOFF pin on CY7C25682KV18?

The DOFF (Double-Off) pin configures read latency mode: when asserted HIGH, it enables DDR II+ operation with 2.5-cycle read latency; when LOW or tied to VSS, it reverts to DDR I-compatible 1-cycle latency. This pin is sampled during power-up initialization and remains static during operation - it is not dynamically switchable mid-operation.

How does the ODT feature work, and what external components does it eliminate?

ODT provides programmable on-die termination for DQ[17:0], BWS[1:0], and K/K inputs using an external ZQ resistor (175–350 Ω). When enabled, it replaces up to 24 discrete 50 Ω or 75 Ω parallel termination resistors, removing associated PCB space, routing complexity, and signal reflection risks - no external termination networks are required.

What is the role of CQ and CQ echo clocks, and why are they critical for system design?

CQ and CQ are free-running, phase-aligned copies of the K and K input clocks, driven out synchronously with read data. They eliminate the need for separate clock forwarding or per-device deskew circuitry, enabling reliable data capture at 1100 MT/s without complex PCB trace length matching - essential for multi-SRAM depth-expanded systems.

Can CY7C25682KV18 operate with 1.5 V I/O supply, and what are the implications?

Yes - VDDQ supports 1.4 V to 1.8 V, explicitly including 1.5 V. At 1.5 V, HSTL output drive strength is reduced versus 1.8 V, but remains compliant with HSTL Class I specifications. System designers must verify timing margins and receiver thresholds, especially when interfacing with 1.5 V FPGA I/O banks operating near VDDQ minima.