Infineon Technologies CY7C1518KV18-250BZI

Overview

CY7C1518KV18-250BZI 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 VDDQ. 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 packet buffering systems.

For engineers reviewing the CY7C1518KV18-250BZI datasheet, CY7C1518KV18-250BZI pinout, CY7C1518KV18-250BZI application, or CY7C1518KV18-250BZI equivalent, key selection considerations include its 1.5-cycle read latency (DOFF = HIGH), programmable output impedance via ZQ, JTAG 1149.1 test access port, and 165-ball FBGA package with 13 × 15 mm footprint.

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. Write data is registered on both K and K edges, while read data is driven synchronously on rising edges of C and C - or K and K in single-clock mode - enabling deterministic timing alignment across memory channels.

It integrates a PLL for accurate data placement relative to echo clocks, supports variable-drive HSTL outputs (1.4 V–VDDQ), and uses asynchronous ZQ calibration to match system bus impedance. The DOFF pin selects between DDR-II mode (1.5-cycle latency) and DDR-I–compatible mode (1-cycle latency), allowing flexible integration into legacy and next-generation controllers.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C36256PFS-25BIN and IS61WV102418BLL-25BLI, CY7C1518KV18-250BZI provides 3.5× higher peak bandwidth, deterministic DDR timing via echo clocks, and on-die impedance tuning - making it uniquely suited for high-speed packet and video buffering where timing predictability and signal integrity are critical.

Availability

CY7C1518KV18-250BZI is available at Aetrix Electronics and suitable for packet buffering in network switches, line-card memory in telecom infrastructure, real-time video frame storage, and radar signal processing requiring stable component supply and long-term industrial availability.

Supply support for CY7C1518KV18-250BZI 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) designs high-performance memory and programmable solutions for industrial, automotive, and communications markets, with emphasis on signal integrity, timing precision, and system-level integration.

CY7C1518KV18 belongs to Cypress's DDR-II synchronous SRAM product line, engineered specifically for high-throughput, low-latency buffering in packet-switched networks and real-time digital signal processing systems where deterministic timing and scalable bandwidth are essential.

FAQ

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

The DOFF pin selects DDR operational mode: when asserted HIGH, the device operates in DDR-II mode with 1.5-cycle read latency and full two-word burst capability; when LOW, it behaves like a DDR-I SRAM with 1-cycle latency and simplified timing. This pin must be statically tied during power-up and cannot be dynamically changed during operation.

Can CY7C1518KV18-250BZI operate without the C and C output clocks?

Yes - the device supports single-clock mode using only K and K for both input sampling and output driving. In this mode, read data is output on the rising edges of K and K instead of C and C, and echo clocks CQ/CQ are generated relative to K. However, deskew capability and maximum timing margin are reduced compared to dual-clock operation.

How is output impedance calibrated using the ZQ pin?

ZQ connects to an external 240 Ω resistor to ground, enabling internal calibration of DQ and CQ driver strength to match 50 Ω transmission lines. The resulting output impedance is set to 0.2 × RQ = 48 Ω. Connecting ZQ directly to VDDQ enables minimum-impedance mode (~30 Ω), while leaving it unconnected or tying to GND violates specification and may cause undefined behavior.

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

No - although both use the same 165-ball FBGA package, their pinouts differ significantly: CY7C1518KV18 has DQ[17:0], BWS[1:0], and 22 address lines (A[21:0]), while CY7C1520KV18 has DQ[35:0], BWS[3:0], and 21 address lines (A[20:0]). Interchangeability requires full PCB redesign and firmware adaptation due to differing data width, byte-select mapping, and address decoding.