Infineon Technologies CY7C1250KV18-450BZXC

Overview

CY7C1250KV18 from Cypress Semiconductor is a 36-Mbit (1 M × 36) DDR II+ synchronous SRAM with 2-word burst architecture, 2.0-cycle read latency, and 450 MHz clock operation. It uses HSTL I/O buffers, supports 1.4–1.8 V I/O supply (VDDQ), and integrates echo clocks (CQ/CQ) and QVLD for precise high-speed data capture in memory subsystems of networking line cards and packet buffer applications.

For engineers reviewing the CY7C1250KV18 datasheet, CY7C1250KV18 pinout, CY7C1250KV18 application, or CY7C1250KV18 equivalent, key selection criteria include its 1 M × 36 organization, 450 MHz K/K clock support, 900 Mbps DDR data rate, DOFF-configurable latency mode, and 165-ball FBGA (13 × 15 × 1.4 mm) package compatibility with high-density PCB layouts.

Technical Context

This SRAM implements a pipelined DDR II+ architecture where addresses are latched on alternate rising edges of K and K, and read/write data is registered on both clock edges. Internal self-timed write circuitry eliminates external write strobes, while synchronous output registers align Q[35:0] to CQ/CQ edges.

The device integrates a PLL for accurate data placement, JTAG 1149.1 test access port, and programmable impedance via ZQ calibration. Its dual-clock timing model requires strict matching between K and K skew, and QVLD provides edge-aligned validity indication synchronized to echo clocks-not to K/K-enabling reliable capture in source-synchronous interfaces.

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 high-bandwidth synchronous SRAM applications.

Compared with AS7C362000B-450BIN and IS61WV102436BLL-450T, CY7C1250KV18 delivers superior timing robustness via CQ/CQ echo clocks and QVLD, enables flexible latency selection via DOFF, and supports modern low-voltage I/O with ZQ calibration-critical for high-reliability, high-density designs.

Availability

CY7C1250KV18 is available at Aetrix Electronics and suitable for packet buffer memory, telecom line card cache, network processor data tables, and high-speed test equipment requiring stable component supply, long-term lifecycle assurance, and consistent FBGA packaging.

Supply support for CY7C1250KV18 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.

CY7C1250KV18 belongs to the QDR II+ SRAM product line, designed specifically for high-bandwidth, low-latency memory subsystems in networking infrastructure, where deterministic timing, source-synchronous interfaces, and multi-voltage I/O compatibility are essential.

FAQ

What is the function of the DOFF pin on CY7C1250KV18?

The DOFF (Data-Off) pin configures read latency mode: when asserted HIGH, it enables 2.0-cycle latency (DDR II+ mode); when LOW, it selects 1-cycle latency (DDR I mode). This setting determines internal pipeline depth and affects timing parameters like tKQH and tKQV. DOFF is sampled synchronously on the rising edge of K and remains effective until changed.

How do CQ and CQ differ from K and K in timing implementation?

CQ and CQ are free-running echo clocks derived from K and phase-aligned to output data edges-not input clocks. They are generated internally and driven out synchronously with Q[35:0], enabling external receivers to latch data using CQ/CQ instead of K/K. This eliminates clock-to-data skew introduced by PCB routing differences between clock and data nets.

Can CY7C1250KV18 operate with VDDQ = 1.5 V while VDD = 1.8 V?

Yes. The device explicitly supports VDDQ from 1.4 V to VDD (1.8 V), so 1.5 V is within specification. This allows interoperability with 1.5 V FPGA I/O banks while maintaining 1.8 V core operation. All HSTL I/O characteristics-including drive strength, input thresholds, and AC timing-are guaranteed across this VDDQ range when VDD is 1.8 V ± 0.1 V.

What is the purpose of the ZQ pin and how is it used?

ZQ connects to an external 240 Ω resistor to ground and enables on-die termination calibration. During initialization or periodic recalibration, the device measures this reference to adjust HSTL output driver impedance, compensating for process, voltage, and temperature variations. Proper ZQ connection is required to meet HSTL output specifications and maintain signal integrity at 450 MHz.