Cypress Semiconductor Corp CY7C25702KV18-400BZC

Overview

CY7C25702KV18 from Cypress Semiconductor is a 72-Mbit synchronous pipelined DDR II+ SRAM with 2M × 36 organization, 2.5-cycle read latency (DOFF = HIGH), 550 MHz clock support, and on-die termination (ODT) for DQ/BWS/K/K inputs - deployed in high-bandwidth networking line cards and packet buffer subsystems.

For engineers reviewing the CY7C25702KV18 datasheet, CY7C25702KV18 pinout, CY7C25702KV18 application, or CY7C25702KV18 equivalent, key selection criteria include burst depth (2-word), echo clock timing (CQ/CQ alignment), QVLD validity signaling, HSTL I/O compatibility, and FBGA-165 package thermal/mechanical constraints.

Technical Context

This device implements a synchronous DDR II+ interface with dual input clocks (K and K) - all address, control, and data inputs registered on rising edges of K or K. Read data is driven on both K and K rising edges, with QVLD edge-aligned to CQ/CQ for precise capture.

The internal architecture uses two 1M × 36 arrays, supports byte-write via four BWS signals (BWS[3:0]), and integrates a PLL for accurate data placement. ODT range selection (RQ/3.33 or RQ/1.66) is controlled by the ODT pin at power-up, with ZQ calibration enabling impedance matching without external resistors.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DDR SRAM applications.

Compared with IDT 72T36120L10PFI and ISSI IS61WV102436BLL-15BLI, CY7C25702KV18 uniquely delivers DDR II+ timing, integrated ODT, and echo-clock–based data capture - enabling higher bandwidth, lower system component count, and reduced FPGA logic overhead in 500+ MHz applications.

Availability

CY7C25702KV18 is available at Aetrix Electronics and suitable for network packet buffers, telecom line card memory, high-speed test equipment memory, and radar signal processing buffers requiring stable component supply across extended product lifecycles.

Supply support for CY7C25702KV18 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 communications, industrial, and automotive markets.

CY7C25702KV18 belongs to the QDR II+ SRAM product line, engineered specifically for deterministic, low-latency, high-bandwidth memory interfacing in packet-switched infrastructure and real-time signal processing systems.

FAQ

What is the function of the DOFF pin?

The DOFF (Double-Off) pin configures the device's 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 mode with 1-cycle latency. This pin is sampled only at power-up and remains latched until reset, allowing system-level trade-offs between bandwidth and timing margin.

How does on-die termination (ODT) work on this SRAM?

ODT applies programmable termination resistance to DQ[35:0], BWS[3:0], K, and K inputs using an internal resistor network calibrated against the ZQ pin. The ODT pin selects between two ranges: LOW sets RQ/3.33 (~72 Ω for 240 Ω ZQ), HIGH sets RQ/1.66 (~144 Ω). This eliminates 28+ external resistors while maintaining signal integrity at 1100 MT/s.

Can CY7C25702KV18 be used with a 400 MHz system clock?

Yes - the device is rated for 400 MHz operation (see Ordering Code suffix "-400BZC"). At 400 MHz, typical operating current is 750 mA (for 2M × 36), and AC timing parameters (e.g., tKQ, tKHK) scale linearly. All features - including ODT, QVLD, and echo clocks - remain fully functional; only maximum bandwidth reduces from 1100 to 800 MT/s.

What is the role of the CQ and CQ echo clocks?

CQ and CQ are free-running output clocks synchronized to the input K clock, with fixed phase alignment to DQ data edges. They serve as dedicated capture clocks for downstream logic (e.g., FPGA input registers), removing skew sensitivity and eliminating the need for dynamic deskew circuits or complex timing closure across multiple SRAM devices in parallel configurations.