Infineon Technologies CY7C1420KV18-250BZXI

Overview

CY7C1420KV18-250BZXI from Cypress Semiconductor is a 36-Mbit (1M × 36) synchronous DDR II SRAM with two-word burst architecture, 250 MHz maximum clock frequency, 1.8 V core supply, HSTL I/O, and echo clocks (CQ/CQ) for precise data capture in high-speed memory subsystems. It operates in DDR-II mode (1.5-cycle read latency when DOFF = HIGH) or DDR-I mode (1-cycle latency when DOFF = LOW), targeting network packet buffering and telecom line-card memory.

For engineers reviewing the CY7C1420KV18-250BZXI datasheet, CY7C1420KV18-250BZXI pinout, CY7C1420KV18-250BZXI application, or CY7C1420KV18-250BZXI equivalent, key selection criteria include burst depth (2×36-bit), dual-clock domain support (K/K and C/C), programmable output impedance via ZQ, JTAG 1149.1 test access, and FBGA-165 package compatibility with high-density PCB layouts.

Technical Context

The device implements a synchronous pipelined architecture with internal burst counter driven by A0, delivering two sequential 36-bit words per access. All address, control, and data inputs are registered on rising edges of K and K clocks, enabling deterministic timing at 250 MHz.

Read data is edge-aligned to C and C output clocks (or K/K in single-clock mode), while echo clocks CQ and CQ-phase-synchronized to C and C-eliminate board-level skew compensation. The integrated PLL ensures accurate data placement, and ZQ pin enables dynamic output impedance tuning to match 50 Ω system buses.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 13 × 15 mm body, 0.8 mm ball pitch, 1.4 mm height, bottom-side thermal pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C33618B-250BIN and IS45S32800J-25BLI, CY7C1420KV18-250BZXI offers deterministic zero-refresh latency, on-die impedance tuning, and source-synchronous echo clocks - making it superior for hard real-time, jitter-sensitive, or high-reliability embedded memory subsystems.

Availability

CY7C1420KV18-250BZXI is available at Aetrix Electronics and suitable for telecom line cards, network packet buffers, baseband processing units, and industrial real-time controllers requiring stable component supply, long-lifecycle support, and guaranteed Pb-free compliance.

Supply support for CY7C1420KV18-250BZXI 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 U.S.-based semiconductor company specializing in high-performance memory, microcontrollers, and connectivity solutions for industrial, automotive, and communications markets.

CY7C1420KV18 belongs to Cypress's DDR II SRAM product line, designed specifically for deterministic, low-jitter, high-bandwidth memory interfacing in networking and telecom infrastructure where burst efficiency and timing predictability outweigh raw density.

FAQ

What is the function of the DOFF pin on CY7C1420KV18-250BZXI?

The DOFF (Data Output OFF) pin selects read latency mode: when asserted HIGH, it enables DDR-II operation with 1.5-cycle read latency; when LOW, it configures DDR-I mode with 1-cycle latency. This setting determines internal pipeline depth and must be held stable during operation - it is not dynamically switchable mid-burst.

Can CY7C1420KV18-250BZXI operate without external C and C clocks?

Yes - the device supports single-clock mode where K and K serve as both input and output clocks. In this mode, read data is driven on K/K edges, and CQ/CQ are generated relative to K/K. However, echo clock benefits (skew cancellation) are lost, and system timing margin decreases significantly above 200 MHz.

How does ZQ calibration affect signal integrity in high-speed designs?

ZQ calibration adjusts the output driver impedance of DQ and CQ pins to match the PCB trace characteristic impedance (typically 50 Ω). Using a 24.9 Ω resistor on ZQ yields ~5 Ω driver impedance (0.2 × RQ), minimizing reflections and improving eye diagram opening - especially critical for clean 500 MT/s DDR signaling without external termination.

Is CY7C1420KV18-250BZXI pin-compatible with CY7C1418KV18-250BZXI?

No - although both share the same 165-ball FBGA package, their pinouts differ significantly: CY7C1418KV18 uses DQ[17:0] and BWS[1:0], while CY7C1420KV18 uses DQ[35:0] and BWS[3:0]. Address mapping also differs (21-bit vs. 20-bit), and BWS pin assignments are reorganized to support 36-bit byte lanes - direct replacement is not possible without PCB redesign.