Infineon Technologies CY7C425-15JXCT

Overview

CY7C425-15JXCT from Cypress Semiconductor is a 1,024 × 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, and operates at 5V ±10% over industrial temperature (–40°C to +85°C). Its dual-port RAM architecture enables real-time flow control in serial communication interfaces and video frame buffering.

For engineers reviewing the CY7C425-15JXCT datasheet, CY7C425-15JXCT pinout, CY7C425-15JXCT application, or CY7C425-15JXCT equivalent, key selection criteria include access time (15 ns), flag timing behavior (tREF = 15 ns), standalone retransmit capability, and compatibility with width/depth expansion topologies using FL/RT, XO/HF, and MR pins.

Technical Context

This FIFO implements a dual-ported static RAM core with separate read and write address pointers, enabling fully asynchronous operation without internal synchronization logic. Flag generation (EF, FF, HF) is combinatorial and synchronized only to respective control edges (R# or W#), ensuring deterministic latency for handshaking.

The device supports three operational modes: standalone (with retransmit via RT input), width expansion (using FL/RT and XO/HF as bidirectional width-control signals), and depth expansion (where XO/HF becomes expansion-out signal). All modes retain independent 50 MHz throughput without added propagation delay stacking.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT7202LA-15JG and AM7202-15JC, CY7C425-15JXCT uniquely retains full retransmit functionality in standalone mode and offers verified PLCC packaging for through-hole prototyping and high-reliability industrial assembly-making it optimal for new designs requiring field-upgradeable packet recovery.

Availability

CY7C425-15JXCT is available at Aetrix Electronics and suitable for industrial serial bridges, video line buffering, protocol translation gateways, and legacy bus interfacing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY7C425-15JXCT 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 SoCs, memory, and interface solutions for industrial, automotive, and consumer applications.

The CY7C4xx FIFO family was designed specifically for high-reliability, low-latency data buffering in mixed-clock-domain systems-emphasizing deterministic flag timing, expandability, and direct TTL compatibility without external level-shifting.

FAQ

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

CY7C425-15JXCT supports independent 50 MHz read and write operations-verified by t_RC = 25 ns and t_WC = 25 ns min. This allows sustained 450 Mbps throughput (9 bits × 50 MHz) without interlock or arbitration logic, provided setup/hold times (t_SD = 8 ns, t_HD = 0 ns) are met in the system design.

Does the Half Full (HF) flag operate identically in all configuration modes?

No-the HF flag is only active in standalone and width expansion modes, where it asserts HIGH at exactly 512 words filled. In depth expansion mode, the same pin functions as Expansion Out (XO), signaling activation to the next FIFO in the chain; HF behavior is disabled and undefined in that topology.

Can the Master Reset (MR) pin be asserted while read or write operations are active?

Yes, but only if both R# and W# are held HIGH during MR assertion-per datasheet page 8, note 11. Violating this condition may cause undefined flag states or pointer misalignment. MR resets pointers and flags synchronously to the next R# or W# edge after deassertion.

Is the CY7C425-15JXCT compatible with 3.3V logic interfaces?

No-it requires a 5.0 V ±10% supply and has TTL-compatible input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V), but its outputs swing rail-to-rail (VOH ≥ 2.4 V, VOL ≤ 0.4 V at specified loads). Direct connection to 3.3V-only devices risks overvoltage damage unless level-shifting circuitry is used.