Cypress Semiconductor Corp CY7C1518KV18-250BZXI

Overview

CY7C1518KV18-250BZXI from Cypress Semiconductor is a 72-Mbit (4M × 18) synchronous DDR-II SRAM with two-word burst architecture, 250 MHz maximum clock frequency, 1.8 V core supply, and HSTL I/O compatible with 1.5 V/1.8 V IO rails. It delivers 900 MB/s peak bandwidth via double-data-rate transfers at 500 Mbps per pin and supports precise timing via dual K/K input clocks and echo clocks CQ/CQ for high-speed data capture in networking and test equipment memory buffers.

For engineers reviewing the CY7C1518KV18-250BZXI datasheet, CY7C1518KV18-250BZXI pinout, CY7C1518KV18-250BZXI application, or CY7C1518KV18-250BZXI equivalent, key selection criteria include its 1.5-cycle read latency (DOFF = HIGH), programmable output drive strength, JTAG 1149.1 boundary scan support, and 165-ball FBGA package with ZQ impedance calibration.

Technical Context

The device implements a synchronous pipelined architecture with internal burst counter driven by A0, latching addresses on alternate rising edges of K and K clocks. Write data is registered on both K and K edges, while read data is driven synchronously to C and C - enabling deskewed system-level timing across multiple SRAMs.

It integrates a PLL for accurate data placement, supports single-clock mode (using K/K only) when C/C are unconnected, and uses ZQ calibration to match output impedance to system bus (0.2 × RQ). DOFF pin selects between DDR-II mode (1.5-cycle latency) and DDR-I–compatible mode (1-cycle latency).

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 Pb-free finish (BZXI suffix).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-bandwidth synchronous SRAM applications.

Compared with AS7C362000B-250BIN and IS61WV102418BLL-250TQLI, CY7C1518KV18-250BZXI uniquely delivers DDR-II burst performance at 1.8 V with integrated impedance control and echo clocks - reducing system-level timing margin risk in high-speed serial data paths.

Availability

CY7C1518KV18-250BZXI is available at Aetrix Electronics and suitable for high-speed packet buffering, test equipment waveform memory, telecom baseband processing, and industrial motion controller FIFO applications requiring stable component supply and long-term obsolescence management.

Supply support for CY7C1518KV18-250BZXI 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) designs high-performance memory and programmable solutions for demanding embedded and communications systems, with focus on reliability, signal integrity, and system-level integration.

CY7C1518KV18 belongs to Cypress's DDR-II synchronous SRAM product line, engineered specifically for applications needing deterministic low-latency burst access, source-synchronous timing, and impedance-matched I/O in high-speed digital systems.

FAQ

What is the function of the DOFF pin on CY7C1518KV18-250BZXI?

The DOFF (DDR Operation Mode Select) pin configures the device's read latency behavior: when asserted HIGH, it enables DDR-II mode with 1.5-cycle read latency; when LOW, it reverts to DDR-I–compatible mode with 1-cycle latency. This pin directly selects internal timing paths and must be held static during operation - it is not sampled dynamically per access.

Can CY7C1518KV18-250BZXI operate without external C and C clocks?

Yes - the device supports single-clock mode where read data is driven on the rising edges of K and K instead of C and C. In this configuration, echo clocks CQ/CQ remain functional and phase-aligned to K/K, preserving their utility for data capture timing. All timing parameters shift to reference K/K edges, and setup/hold margins must be re-validated per the datasheet's single-clock timing tables.

How does ZQ calibration work, and what resistor value is required?

ZQ calibration uses an external resistor (RQ) connected between the ZQ pin and ground to set output driver impedance to 0.2 × RQ. For standard 50 Ω PCB traces, a 240 Ω resistor yields 48 Ω output impedance. The device performs calibration at power-up and optionally on command via JTAG; it cannot be left floating or tied to VSS, and direct connection to VDDQ enables minimum-impedance mode (~30 Ω).

Is CY7C1518KV18-250BZXI pin-compatible with other densities in the CY7C15xxKV18 family?

No - CY7C1518KV18-250BZXI (4M × 18) is not pin-compatible with CY7C1520KV18 (2M × 36), despite shared package and signal naming. Pin functions differ significantly: BWS[1:0] vs. BWS[3:0], DQ[17:0] vs. DQ[35:0], and distinct address bit counts (A[21:0] vs. A[20:0]). Layout reuse requires full redesign; no mechanical or electrical drop-in replacement exists within the family.