Infineon Technologies CY7C433-15JXCT

Overview

CY7C433-15JXCT from Cypress Semiconductor is a 4,096 × 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 (EF), Full (FF), and Half Full (HF) flags, and operates at 5V ±10% over industrial temperature (–40°C to +85°C). It is commonly deployed in telecom line cards for packet buffering and protocol translation.

For engineers reviewing the CY7C433-15JXCT datasheet, CY7C433-15JXCT pinout, CY7C433-15JXCT application, or CY7C433-15JXCT equivalent, key selection criteria include its 4K×9 depth/width configuration, 15 ns access time, standalone retransmit capability, and compatibility with width/depth expansion topologies using XI, XO/HF, and FL/RT pins.

Technical Context

This FIFO implements dual-ported RAM architecture with separate read and write address pointers, enabling true asynchronous operation without internal arbitration. Its flag logic generates EF, FF, and HF outputs with guaranteed timing relative to read/write strobes - tREF ≤25 ns, tWFF ≤25 ns - ensuring reliable handshaking in high-speed interfaces.

The device supports three operational modes: standalone (with retransmit via RT input), width expansion (using XI/XO/HF for parallel data bus extension), and depth expansion (where XO drives MR of cascaded devices). All control inputs (R, W, MR, RT) are TTL-compatible with VIH ≥2.2 V and VIL ≤0.8 V under industrial conditions.

Key Specifications

Pinout & Package

Package: 32-pin PLCC (Plastic Leaded Chip Carrier), 11.43 mm × 13.97 mm, JEDEC MS-026AC compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT7204L15J and AM7204-15JC, CY7C433-15JXCT offers native TTL compatibility, integrated retransmit functionality, and RoHS-compliant packaging - making it optimal for cost-sensitive industrial telecom and legacy bus bridging where signal integrity and protocol flexibility are prioritized over minimal power savings.

Availability

CY7C433-15JXCT is available at Aetrix Electronics and suitable for telecom infrastructure, industrial PLC backplanes, legacy bus protocol translators, and automated test equipment requiring stable component supply and long-term obsolescence management.

Supply support for CY7C433-15JXCT 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 U.S.-based semiconductor company specializing in programmable solutions, memory, and USB/USB-C controllers.

The CY7C4xx FIFO family was designed specifically for high-reliability, asynchronous data buffering in industrial and telecom systems where deterministic latency, flag-driven flow control, and seamless expansion are required.

FAQ

What is the function of the FL/RT pin in standalone mode?

In standalone mode, FL/RT serves as the Retransmit (RT) input. When pulled LOW while both R and W are HIGH, the FIFO retransmits the most recently read word without advancing the read pointer. This enables error recovery and repeated transmission without host CPU overhead - confirmed in Functional Description section of Rev. *B datasheet, page 2.

Does CY7C433-15JXCT support depth expansion with more than two devices?

Yes - the device supports unlimited depth expansion using the XO/HF and MR pins. Each stage's XO drives the next stage's MR, and control signals (R, W, MR) are wired in parallel. Propagation delay remains constant per stage, preserving 50 MHz throughput regardless of cascade length - verified in "Depth Expansion Technique" description on page 2.

Is the Half Full (HF) flag available in all configurations?

No - HF is valid only in standalone and width expansion modes. In depth expansion, the same pin functions as Expansion Out (XO) to trigger the next FIFO's master reset. This functional multiplexing is explicitly defined in the Pin Configurations diagram and Functional Description text on page 2.

What is the maximum capacitive load the Q0–Q8 outputs can drive?

The outputs are characterized for 30 pF total load capacitance (including scope probe and fixture), with timing parameters (tLZR, tDVR, tHZR) specified under that condition. Driving >30 pF may violate setup/hold windows or increase propagation delay beyond datasheet limits - see AC Test Loads and Waveforms figure on page 5.