Infineon Technologies CY7C1426AV18-250BZC

Overview

CY7C1426AV18-250BZC from Cypress Semiconductor is a 36-Mbit QDR-II SRAM with 4M × 9 organization, 250 MHz maximum operating frequency, 1.8 V core supply (±0.1 V), and 1.4–1.8 V I/O supply (VDDQ). It implements separate read/write ports with DDR interfaces on both, enabling concurrent transactions in high-bandwidth networking buffers and packet memory applications.

For engineers reviewing the CY7C1426AV18-250BZC datasheet, CY7C1426AV18-250BZC pinout, CY7C1426AV18-250BZC application, or CY7C1426AV18-250BZC equivalent, key selection criteria include burst depth (4-word), echo clock support (CQ/CQ), HSTL-compatible I/O drive, JTAG 1149.1 test access, and DLL-based data alignment for 600 Mbps DDR timing at 250 MHz K-clock.

Technical Context

The device uses synchronous pipelined architecture with independent K/K input clocks for address/data capture and C/C output clocks for data launch-enabling precise DDR timing without bus turnaround. Its Delay Lock Loop (DLL) aligns echo clocks (CQ/CQ) to output data edges, reducing setup/hold uncertainty in high-speed systems.

Address inputs are multiplexed across read and write ports, latched on alternate rising edges of K; each access delivers four sequential 9-bit words. Write operations are self-timed and synchronized to K, while read outputs are registered to C/C, supporting full data coherency and depth expansion via RPS/WPS and BWS[0] control.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 15 mm × 17 mm × 1.4 mm, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C362000B-250BIN and IS61WV102418B-250BLI, CY7C1426AV18-250BZC uniquely delivers concurrent DDR throughput, echo-clock–assisted capture, and HSTL signaling - making it the only option for deterministic 10G+ packet memory subsystems.

Availability

CY7C1426AV18-250BZC is available at Aetrix Electronics and suitable for packet buffer memory, network switch fabric, and telecom baseband processing requiring stable component supply and long-term industrial lifecycle support.

Supply support for CY7C1426AV18-250BZC 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 networking, automotive, and industrial systems, with emphasis on signal integrity and timing precision.

CY7C1426AV18 belongs to the QDR-II SRAM product line, engineered specifically for deterministic, low-latency, concurrent-access memory subsystems in high-speed communications infrastructure.

FAQ

What is the function of the ZQ pin, and how must it be connected?

The ZQ pin calibrates output driver impedance for Q[8:0], CQ, and CQ signals. It must be connected to a 240 Ω resistor tied to ground to set nominal 48 Ω output impedance matching standard 50 Ω PCB traces. Direct connection to VDDQ enables minimum impedance mode (≈35 Ω); floating or grounding ZQ is prohibited and causes undefined drive strength.

Can CY7C1426AV18-250BZC operate without the DLL enabled?

Yes - asserting DOFF low disables the DLL, switching the device to asynchronous output timing mode. In this mode, CQ/CQ become disabled, and data valid window shrinks significantly; maximum operating frequency drops to 167 MHz, and setup/hold margins increase by ~1.2 ns. This mode is intended only for debug or legacy controller compatibility, not production use.

How does the 4-word burst architecture affect address bus utilization?

Each read or write access transfers four consecutive 9-bit words using a single 20-bit address (A[19:0]). The internal address counter increments automatically after each word, eliminating need for external address sequencing. This reduces effective address bus toggle rate by 75% versus single-word access - lowering EMI, routing congestion, and timing closure effort on dense backplanes.

Is BWS0 pin required for full 9-bit writes, or can it be omitted?

BWS0 is mandatory for write enable control: when deasserted (high), all D[8:0] inputs are ignored regardless of WPS state. For full 9-bit writes, BWS0 must be asserted low synchronously with WPS and data. Leaving BWS0 unconnected or tied high prevents any write operation - the pin is not optional and has no default-active behavior.