Cypress Semiconductor Corp CY7C1520KV18-250BZI

Overview

CY7C1520KV18-250BZI from Cypress Semiconductor is a 72-Mbit synchronous DDR-II SRAM configured as 2M × 36, operating at 250 MHz with 500 MHz effective data rate (DDR), 1.8 V core supply, HSTL I/O, and integrated echo clocks (CQ/CQ) for precise high-speed data capture in networking packet buffers and telecom line cards.

For engineers reviewing the CY7C1520KV18-250BZI datasheet, CY7C1520KV18-250BZI pinout, CY7C1520KV18-250BZI application, or CY7C1520KV18-250BZI equivalent, key selection criteria include burst-mode latency control via DOFF, dual-clock domain timing (K/K and C/C), 165-ball FBGA package compatibility, and JTAG 1149.1 test access support.

Technical Context

This device implements a two-word synchronous burst architecture with internal pipelining: address latching occurs on alternating rising edges of K and K, while write data is registered on both K and K edges. Read data is driven on rising edges of C and C - not K/K - enabling skew-compensated output timing.

The burst counter uses A0 to generate sequential 36-bit word addresses; DOFF selects between 1.5-cycle (HIGH) and 1-cycle (LOW) read latency. All I/O uses HSTL-compatible drivers with programmable impedance via ZQ pin tied to external resistor or VDDQ.

Key Specifications

Pinout & Package

Package: 165-ball fine-pitch ball grid array (FBGA), 13 × 15 mm body, 1.4 mm height, 0.8 mm ball pitch, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C362000B-250BIN and IS61WV204836BLL-250TQLI, CY7C1520KV18-250BZI uniquely balances 500 MT/s DDR performance with built-in echo clocks and programmable latency-reducing system-level timing validation effort while maintaining 1.8 V compatibility.

Availability

CY7C1520KV18-250BZI is available at Aetrix Electronics and suitable for networking packet buffers, telecom line cards, high-speed test equipment, and radar signal processing buffers requiring stable component supply across extended product lifecycles.

Supply support for CY7C1520KV18-250BZI 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.

CY7C1520KV18 belongs to Cypress's DDR-II synchronous SRAM product line, designed specifically for bandwidth-constrained, low-latency applications in packet-switched infrastructure where deterministic timing and signal integrity are critical.

FAQ

What is the function of the DOFF pin on CY7C1520KV18-250BZI?

The DOFF (Data-Off) pin configures read latency mode: when asserted HIGH, it enables 1.5-cycle DDR-II latency for improved timing margin; when LOW, it reverts to 1-cycle DDR-I latency for maximum throughput. This setting is sampled synchronously on the K clock edge and remains active until changed.

Can CY7C1520KV18-250BZI operate without external C and C clocks?

Yes - in single-clock mode, the device uses K and K as both input and output clocks. In this configuration, read data is driven on K/K edges instead of C/C, and CQ/CQ are generated relative to K/K. However, echo-clock benefits (skew compensation) are lost, limiting reliable operation to ≤300 MT/s.

How does ZQ pin calibration affect signal integrity?

ZQ connects to an external resistor (typically 240 Ω) to ground, calibrating DQ and CQ output driver impedance to 48 Ω (0.2 × 240 Ω). This matches standard PCB trace impedances, minimizing reflections and ensuring clean eye diagrams at 500 MT/s - critical for error-free operation in high-speed memory channels.

Is CY7C1520KV18-250BZI pin-compatible with CY7C1518KV18-250BZI?

No - although both use the same 165-ball FBGA package, pin assignments differ significantly: CY7C1518KV18 has DQ[17:0], BWS[1:0], and 22 address lines (A[21:0]), while CY7C1520KV18 uses DQ[35:0], BWS[3:0], and 21 address lines (A[20:0]). Direct substitution requires PCB redesign.