Cypress Semiconductor Corp CY7C1523KV18-250BZXC

Overview

CY7C1523KV18-250BZXC from Cypress Semiconductor is a 72-Mbit (4M × 18) DDR II Synchronous Pipelined SRAM with Separate I/O architecture, operating at 250 MHz clock frequency and delivering 500 MHz double-data-rate throughput. It features two-word burst reads/writes, echo clocks (CQ/CQ), programmable impedance via ZQ, and dual input/output clock domains (K/K and C/C) for precise timing control in high-speed memory subsystems used in network packet buffers and FPGA co-processor caches.

For engineers reviewing the CY7C1523KV18-250BZXC datasheet, CY7C1523KV18-250BZXC pinout, CY7C1523KV18-250BZXC application, or CY7C1523KV18-250BZXC equivalent, key selection criteria include DDR II SIO timing compliance, 1.8 V core/1.5–1.8 V I/O flexibility, DOFF-controlled latency mode switching (1-cycle vs. 1.5-cycle read), HSTL-compatible drive strength, and JTAG 1149.1 test access support.

Technical Context

The device implements a synchronous pipelined architecture with independent read and write ports sharing a common 21-bit address bus. Read and write addresses are latched on alternate rising edges of K/K, enabling continuous burst operation without bus turnaround. Internal self-timed write circuitry eliminates external write pulse timing constraints.

DDR II SIO operation relies on matched output clocks (C/C) and echo clocks (CQ/CQ) to deskew data capture across multiple devices. The PLL enables accurate data placement when DOFF is HIGH; disabling it via DOFF LOW reverts behavior to DDR-I mode with 1-cycle latency and ≤167 MHz max frequency.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 13 mm × 15 mm × 1.4 mm, RoHS-compliant, Pb-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C3256B-15JIN and IS61WV102418BLL-10BLI, CY7C1523KV18-250BZXC uniquely delivers 72-Mbit density with DDR-II SIO, echo clocks, and programmable impedance - making it irreplaceable for systems demanding >400 MB/s sustained throughput with sub-6 ns deterministic latency.

Availability

CY7C1523KV18-250BZXC is available at Aetrix Electronics and suitable for network packet buffers, FPGA co-processor caches, telecom baseband processing, and industrial real-time controllers requiring stable component supply and long-term lifecycle assurance.

Supply support for CY7C1523KV18-250BZXC 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 infrastructure markets.

The CY7C1523KV18 belongs to Cypress's DDR II SIO SRAM product line, engineered specifically for deterministic, high-bandwidth memory interfacing in FPGA- and ASIC-based systems where bus turnaround overhead and clock skew must be eliminated.

FAQ

What is the function of the DOFF pin?

The DOFF pin controls internal PLL operation: when asserted HIGH, the device operates in DDR-II mode with 1.5-cycle read latency and 250 MHz maximum frequency; when asserted LOW, the PLL is disabled and the device reverts to DDR-I timing with 1-cycle latency and ≤167 MHz operation. Pull-up resistor (≤10 kΩ to VDDQ) is required for normal DDR-II use.

How does the ZQ pin affect output drive strength?

ZQ connects to an external resistor (RQ) tied to ground, enabling on-die calibration of HSTL output drivers to 0.2 × RQ. This matches output impedance to PCB trace impedance (typically 50 Ω), minimizing reflections and improving signal integrity. Connecting ZQ directly to VDDQ enables minimum impedance mode; floating or grounding ZQ is prohibited.

Can C and C clocks be omitted in system design?

Yes - when C and C are not provided, the device uses K and K as output clocks (single-clock mode). In this configuration, Q[17:0] data is driven on rising edges of K/K, and CQ/CQ are generated relative to K/K. Echo clock functionality remains active, but deskewing capability across multiple devices is reduced compared to dual-clock operation.

What is the role of BWS0 and BWS1 in byte write operations?

BWS0 and BWS1 are active-LOW byte write select signals that control which 9-bit segments of D[17:0] are written: BWS0 enables D[8:0], BWS1 enables D[17:9]. Both must be LOW to write full 18-bit words; asserting either HIGH preserves corresponding byte contents during partial writes - essential for efficient metadata updates without full-word overwrites.