Infineon Technologies CY7C4261-15JXC

Overview

CY7C4261-15JXC from Cypress Semiconductor is a 16K × 9 deep-synchronous FIFO memory IC with asynchronous read/write capability, 100 MHz max clock frequency (10 ns cycle time), 35 mA active supply current, and programmable Almost Empty/Almost Full flags synchronized to RCLK/WCLK respectively. It serves as a high-speed data buffer in multiprocessor interconnects and serial communications interfaces.

For engineers reviewing the CY7C4261-15JXC datasheet, CY7C4261-15JXC pinout, CY7C4261-15JXC application, or CY7C4261-15JXC equivalent, key selection criteria include synchronous flag timing alignment, dual-write-enable configuration flexibility, 9-bit bus width scalability, and PLCC/TQFP package compatibility with legacy CY7C42X1 designs.

Technical Context

The CY7C4261-15JXC implements a dual-clock FIFO architecture with independent WCLK and RCLK domains, enabling true asynchronous operation. Its 16K × 9 SRAM array uses separate read/write pointers, reset-controlled initialization, and edge-triggered enable logic (WEN1/WEN2/LD, REN1/REN2) for deterministic data flow control.

Flag generation is fully synchronous: EF and PAE update on RCLK edges; FF and PAF update on WCLK edges. The WEN2/LD pin supports dual operational modes-second write enable or flag-offset register load-determined at power-on reset state, enabling configurable depth expansion or programmable threshold behavior.

Key Specifications

Pinout & Package

Package: 32-pin PLCC (plastic leaded chip carrier) and 32-pin TQFP - both surface-mount, RoHS-compliant, with center power/ground pins for noise reduction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar deep-synchronous FIFO applications.

Compared with IDT72201L15TPG and CY7C4265-15JXC, the CY7C4261-15JXC offers unique configurability via WEN2/LD mode selection and factory-default programmable flags - critical for adaptive buffer management in variable-latency systems.

Availability

CY7C4261-15JXC is available at Aetrix Electronics and suitable for high-speed data acquisition, multiprocessor interconnect, and serial communications buffering requiring stable component supply across long-lifecycle industrial programs.

Supply support for CY7C4261-15JXC 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 mixed-signal ICs, memory, and programmable solutions for embedded systems.

The CY7C4261 belongs to Cypress's Deep Sync FIFO product line, designed specifically for deterministic, low-latency data buffering in clock-domain-crossing applications where metastability avoidance and precise flag timing are critical.

FAQ

Is CY7C4261-15JXC pin-compatible with CY7C4251 or CY7C4241?

No. CY7C4261-15JXC is pin-compatible only with CY7C4261/71 family members and IDT72201/21/31/41/51 series. CY7C4251 (8K × 9) and CY7C4241 (4K × 9) use different pinouts and lack WEN2/LD functionality, making them incompatible despite shared package footprint.

What is the minimum pulse width requirement for RS (reset) signal?

The RS pulse must remain LOW for ≥20 ns to ensure reliable reset assertion. After release, EF becomes valid within tRSF = 15 ns (max) relative to the rising edge of RS, and the FIFO enters guaranteed empty state with all pointers cleared.

Can RCLK and WCLK be tied together for single-clock operation?

Yes. RCLK and WCLK may be connected to the same clock source for synchronous operation. In this mode, read and write operations occur on the same edge, and EF/FF flags remain valid - but PAE/PAF retain their respective clock-domain synchronization (RCLK for PAE, WCLK for PAF).

Does CY7C4261-15JXC support hot insertion or live swapping?

No. The device lacks hot-swap protection circuitry. Power sequencing must follow VCC before applying clocks or control signals, and RS must be asserted before enabling WEN/REN. Violating this risks undefined flag states or data corruption.