Infineon Technologies CY7C429-10AXC

Overview

CY7C429-10AXC from Cypress Semiconductor is a 2,048 × 9-bit asynchronous FIFO memory IC used for buffering data between mismatched clock domains or burst-to-continuous data streams. It supports independent 50 MHz read/write operations, features Empty/Full/Half Full flags, TTL-compatible I/O, and operates at 5V ±10% over commercial temperature (0°C to +70°C). It is commonly deployed in serial communication interfaces, video frame buffering, and legacy bus bridging applications.

For engineers reviewing the CY7C429-10AXC datasheet, CY7C429-10AXC pinout, CY7C429-10AXC application, or CY7C429-10AXC equivalent, key selection criteria include its 2K×9 depth/width configuration, 10 ns access time, standalone retransmit capability, and compatibility with width/depth expansion topologies using XI/XO and FL/RT control signals.

Technical Context

This FIFO implements dual-ported RAM architecture with separate read and write address pointers, enabling true asynchronous operation. The device uses advanced 0.65-µm P-well CMOS technology and includes on-chip flag logic for EF (Empty), FF (Full), and HF (Half Full) status monitoring - with HF repurposed as Expansion Out (XO) in depth-expansion mode.

Control logic supports retransmit functionality via the FL/RT pin, requiring both R and W high during retransmit initiation; data is then clocked out using R pulses. The MR (Master Reset) input synchronously clears all internal pointers and flags, ensuring deterministic startup behavior across power-up or error recovery sequences.

Key Specifications

Pinout & Package

The CY7C429-10AXC is housed in a 32-pin PLCC (Plastic Leaded Chip Carrier) package with 11.43 mm × 11.43 mm footprint and 1.27 mm lead pitch. This surface-mount package supports automated assembly and offers robust thermal and mechanical performance for mid-volume production.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar asynchronous FIFO applications.

Compared with IDT7203 and AM7203, the CY7C429-10AXC uniquely integrates retransmit functionality and HF/XO dual-mode operation within the same 32-pin PLCC footprint, offering greater flexibility in depth-expansion architectures and reducing external component count in protocol-recovery systems.

Availability

CY7C429-10AXC is available at Aetrix Electronics and suitable for serial communication bridges, video line buffering, legacy bus interfacing, and automated test equipment requiring stable component supply and long-term obsolescence management.

Supply support for CY7C429-10AXC 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 Corporation, now part of Infineon Technologies, is a fabless semiconductor company specializing in programmable system-on-chip (PSoC), memory, and interface solutions for industrial, automotive, and consumer markets.

The CY7C4xx FIFO family was designed specifically for high-reliability, low-latency data buffering in mixed-signal and legacy digital systems - emphasizing pin compatibility, expandability, and deterministic timing behavior over software-configurable features.

FAQ

What is the maximum supported clock frequency for independent read and write operations?

The CY7C429-10AXC supports up to 50 MHz for both read and write operations independently, as confirmed by its 10 ns access time (t_A) and 20 ns read/write cycle time (t_RC/t_WC). This rating applies under commercial conditions (V_CC = 5V ±10%, T_A = 0°C to +70°C) with proper signal integrity and load capacitance ≤30 pF.

How does the FL/RT pin function in standalone versus expanded configurations?

In standalone mode, FL/RT acts as a retransmit control: pulling it LOW while R and W are HIGH enables repeated output of the last-read data word. In width-expansion mode, it retains retransmit function; in depth-expansion mode, it serves as an expansion input (XI) to receive the XO signal from the preceding FIFO in the chain.

Can the CY7C429-10AXC operate with a 3.3V supply?

No - the CY7C429-10AXC is specified exclusively for 5V ±10% operation (4.5V to 5.5V). Its input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V) and output drive strength are optimized for TTL/5V CMOS logic families. Using 3.3V violates absolute maximum ratings and will result in undefined flag behavior and potential latch-up.

Is the Half Full (HF) flag usable in depth-expansion topologies?

No - in depth-expansion configurations, the HF pin is repurposed as Expansion Out (XO) and no longer reflects half-full status. The device's internal flag logic disables HF assertion in this mode; instead, XO provides timing-coordinated activation signaling to the next FIFO in the cascade, ensuring atomic depth extension without throughput penalty.