Cypress Semiconductor Corp CY7C1518KV18-300BZI

Overview

CY7C1518KV18-300BZI from Cypress Semiconductor is a 72-Mbit (4M × 18) synchronous DDR-II SRAM with two-word burst architecture, 333 MHz clock operation, 1.8 V core supply, HSTL I/O, and 165-ball FBGA (13 × 15 × 1.4 mm) packaging. It delivers 666 MHz effective data rate via double-data-rate interface and supports configurable read latency (1 or 1.5 cycles) via DOFF pin for high-bandwidth buffering in network packet processors.

For engineers reviewing the CY7C1518KV18-300BZI datasheet, CY7C1518KV18-300BZI pinout, CY7C1518KV18-300BZI application, or CY7C1518KV18-300BZI equivalent, key selection criteria include DDR-II timing compliance, echo clock (CQ/CQ) synchronization capability, dual-clock domain support (K/K and C/C), burst-addressed 18-bit data width, and JTAG 1149.1 test access port integration.

Technical Context

This SRAM 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 output-synchronized to C and C (or K/K in single-clock mode), enabling precise timing control in high-speed memory subsystems.

The device integrates a PLL for accurate data placement, echo clocks (CQ/CQ) referenced to C/C for simplified system-level data capture, and programmable output impedance via ZQ pin (0.2 × RQ calibration). DOFF pin selects between DDR-I mode (1-cycle read latency, DOFF = LOW) and DDR-II mode (1.5-cycle read latency, DOFF = HIGH).

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, Pb-free compatible.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IS61WV102418BLL-10BLI and 23LC1024-I/P, CY7C1518KV18-300BZI uniquely delivers DDR-II burst bandwidth, echo-clock–assisted data capture, and JTAG testability - making it irreplaceable in high-throughput, timing-critical memory subsystems.

Availability

CY7C1518KV18-300BZI is available at Aetrix Electronics and suitable for network packet buffering, telecom line card memory, high-speed test equipment memory, and avionics data acquisition buffer applications requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for CY7C1518KV18-300BZI 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.

CY7C1518KV18 belongs to Cypress's DDR-II synchronous SRAM product line, engineered specifically for deterministic, high-bandwidth buffering in packet-processing and real-time signal acquisition systems where traditional DRAM latency or asynchronous SRAM bandwidth is insufficient.

FAQ

What is the function of the DOFF pin on CY7C1518KV18-300BZI?

The DOFF (Data Output OFF) pin configures read latency mode: when asserted HIGH, it enables DDR-II operation with 1.5-cycle read latency; when LOW, it enables DDR-I mode with 1-cycle latency. This selection directly impacts timing budget allocation in the memory controller and must be set before initialization. The pin is sampled synchronously on the rising edge of K.

Can CY7C1518KV18-300BZI operate without external C and C clocks?

Yes - the device supports single-clock mode using only K and K for both input and output timing. In this mode, read data is driven on K/K edges instead of C/C, and echo clocks CQ/CQ are generated relative to K/K. However, this sacrifices the flight-time deskewing benefit of dedicated output clocks and reduces maximum achievable system timing margin.

How is output impedance calibrated using the ZQ pin?

ZQ connects to an external precision resistor (RQ) tied to ground; the device measures RQ and sets all output drivers (DQ, CQ, CQ) to 0.2 × RQ impedance. This calibration occurs automatically at power-up and can be retriggered via JTAG. Connecting ZQ directly to VDDQ enables minimum impedance mode (≈20 Ω), but grounding or leaving it floating is prohibited.

Is CY7C1518KV18-300BZI pin-compatible with CY7C1520KV18-300BZI?

No - although both share the same 165-ball FBGA footprint, their pinouts differ significantly. CY7C1518KV18 uses 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]). Signal assignments for BWS, DQ, and address pins are not interchangeable; PCB layout is not reusable between the two.