Cypress Semiconductor Corp CY7C1518KV18-300BZC

Overview

CY7C1518KV18-300BZC from Cypress Semiconductor is a 72-Mbit (4M × 18) synchronous DDR-II SRAM with two-word burst architecture, 333 MHz clock support, 1.8 V core supply, HSTL I/O, and 165-ball FBGA package. It delivers 666 MHz effective data rate via double-data-rate interface, uses dual K/K input clocks for address/data capture, and supports configurable 1-cycle (DOFF = LOW) or 1.5-cycle (DOFF = HIGH) read latency in high-bandwidth networking buffers.

For engineers reviewing the CY7C1518KV18-300BZC datasheet, CY7C1518KV18-300BZC pinout, CY7C1518KV18-300BZC application, or CY7C1518KV18-300BZC equivalent, key selection criteria include DDR-II timing compliance, echo clock (CQ/CQ) synchronization capability, byte-write select (BWS0/BWS1) granularity, and 165-ball FBGA layout compatibility with high-speed PCB routing constraints.

Technical Context

The device implements a pipelined synchronous 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 clocks - enabling precise deskewing across multi-device memory subsystems.

It integrates a PLL for accurate data placement, JTAG 1149.1 TAP for boundary scan, and ZQ impedance calibration referenced to external resistor. Echo clocks CQ/CQ are free-running and phase-aligned to C/C, eliminating per-device capture timing margins in systems with distributed DDR SRAM banks.

Key Specifications

Pinout & Package

Package: 165-ball fine-pitch ball grid array (FBGA), 13 mm × 15 mm × 1.4 mm body, RoHS-compliant, Pb-free option available.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C3256A-15JCIN and IS61WV102418BLL-10BLI, CY7C1518KV18-300BZC uniquely delivers DDR-II timing, echo-clock–assisted capture, and ZQ-calibrated outputs - making it the only viable choice for new 10 Gbps+ packet buffer and baseband memory subsystems requiring deterministic sub-2-ns timing alignment.

Availability

CY7C1518KV18-300BZC is available at Aetrix Electronics and suitable for telecom line card buffer, high-speed packet switch, and industrial real-time controller applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for CY7C1518KV18-300BZC 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 programmable logic solutions for industrial, automotive, and communications markets.

CY7C1518KV18 belongs to Cypress's DDR-II synchronous SRAM product line, engineered specifically for deterministic, high-throughput buffering in packet-switched networks and real-time signal processing systems where timing predictability outweighs cost-per-bit optimization.

FAQ

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

The DOFF (Data Output OFF) pin configures read latency mode: when asserted HIGH, it enables DDR-II operation with 1.5-cycle read latency and enhanced timing margin; when LOW, it reverts to DDR-I behavior with 1-cycle latency. This pin directly affects controller pipeline depth and must be tied to a fixed voltage (VDD or VSS) - not left floating - to ensure deterministic timing behavior across temperature and voltage corners.

Can CY7C1518KV18-300BZC operate with only K clock (no K, C, or C)?

Yes - the device supports single-clock mode where K serves as both input and output clock: address and control signals are latched on K rising edges, and read data is driven on the same K edges. However, this sacrifices DDR bandwidth and eliminates echo-clock deskew capability, limiting maximum reliable data rate to ~333 MT/s and increasing timing closure difficulty in multi-device systems.

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

ZQ pin connects to an external precision resistor (RQ) tied to ground; the device measures RQ and scales its output drivers to 0.2 × RQ. For standard 50 Ω PCB traces, a 240 Ω ±1% resistor is used (0.2 × 240 Ω = 48 Ω). Calibration occurs automatically at power-up and can be retriggered via JTAG. Direct connection to VDDQ enables minimum-impedance mode (~30 Ω), but grounding or leaving ZQ unconnected is prohibited.

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

No - although both use 165-ball FBGA packages, their pinouts differ significantly: CY7C1518KV18 has DQ[17:0], BWS0/BWS1, and 22 address lines (A[21:0]), while CY7C1520KV18 has DQ[35:0], BWS0–BWS3, and 21 address lines (A[20:0]). The ball assignments for data, byte-select, and address signals are not interchangeable; PCB layout and controller firmware must be redesigned for migration.