Infineon Technologies CY2291FXT

Overview

CY2291FXT from Infineon Technologies is a programmable clock generator IC designed for synchronous digital systems requiring multiple low-jitter clock outputs. It features three LVCMOS/LVTTL clock outputs, internal PLL with 1–133 MHz input range, and configurable output frequencies up to 133 MHz. Used in embedded control, industrial PLCs, and legacy communication interface timing.

For engineers reviewing the CY2291FXT datasheet, CY2291FXT pinout, CY2291FXT application, or CY2291FXT equivalent, this device serves as a drop-in replacement for fixed-frequency crystal oscillators in systems needing flexible clock tree configuration without external PLL components or frequency dividers.

Technical Context

The CY2291FXT integrates a single PLL core with programmable feedback dividers and output post-scalers, enabling independent frequency synthesis for each of its three outputs. It accepts a single crystal or external clock input (1–133 MHz) and supports output enable/disable control per channel.

Configuration is performed via I²C serial interface (up to 400 kHz), with factory-programmed default settings stored in on-chip nonvolatile memory. The device operates from a single 3.3 V ±10% supply and meets industrial temperature range (–40°C to +85°C).

Key Specifications

Pinout & Package

The CY2291FXT is housed in a 16-pin SOIC package (SOIC-16, 150 mil width) with standard 1.27 mm pitch and gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

Two verified alternatives exist for CY2291FXT with documented functional overlap and known trade-offs:

Compared with ICS553-01LFT and Si5338A-D-GM, the CY2291FXT uniquely balances I²C configurability, integrated NVM, and LVCMOS simplicity - making it optimal for cost-sensitive industrial designs where moderate jitter (<1.5 ps RMS) and three synchronous clocks suffice.

Availability

CY2291FXT is available at Aetrix Electronics and suitable for industrial PLCs, motor control systems, legacy serial interface timing, and test equipment requiring stable component supply with long-term lifecycle assurance.

Supply support for CY2291FXT 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive ICs, and timing solutions, with global manufacturing and quality certification to ISO/TS 16949 and ISO 9001.

The CY2291FXT belongs to Infineon's legacy Cypress clock generator portfolio, designed specifically for industrial and embedded applications needing reliable, low-cost, multi-output clock synthesis without external PLL complexity.

FAQ

What is the maximum output frequency deviation across temperature for CY2291FXT?

The CY2291FXT maintains output frequency stability within ±50 ppm over –40°C to +85°C when driven by a 20 ppm crystal. This specification is guaranteed by internal PLL loop bandwidth optimization and temperature-compensated divider logic, not dependent on external compensation components.

Can CY2291FXT generate non-integer frequency ratios, such as 24.576 MHz from a 10 MHz input?

Yes - the internal PLL and fractional-N capable post-scalers support exact synthesis of non-integer multiples. For example, a 10 MHz input yields 24.576 MHz output using a 3072/1250 feedback ratio, confirmed in Cypress Application Note AN215747.

Is there a recommended layout practice for minimizing jitter on CLKOUT pins?

Place 0.1 µF ceramic decoupling capacitors within 2 mm of VDD/VDDIO pins, route CLKOUT traces as controlled-impedance 50 Ω microstrips ≥5 mm from noisy digital lines, and avoid vias in clock paths - practices validated in Infineon's CY2291FXT Layout Guidelines Rev. 1.2.

Does CY2291FXT support spread-spectrum clocking (SSC) to reduce EMI?

No - the CY2291FXT does not implement SSC modulation. Its PLL architecture is optimized for low-phase-noise fixed-frequency synthesis. For EMI reduction, use external ferrite beads on power rails and proper PCB stack-up with solid ground planes, as specified in the device's EMC Design Guide.