Infineon Technologies CY24271ZXCT

Overview

CY24271ZXCT from Infineon Technologies is a programmable clock generator IC designed for high-precision timing in automotive and industrial control systems. It delivers three LVCMOS clock outputs with ±50 ppm frequency accuracy, 1.8 V core supply, and integrated PLL with fractional-N synthesis supporting output frequencies from 1 MHz to 200 MHz. Used in engine control units (ECUs) for synchronizing microcontroller peripherals and sensor interfaces.

For engineers reviewing the CY24271ZXCT datasheet, CY24271ZXCT pinout, CY24271ZXCT application, or CY24271ZXCT equivalent, key selection criteria include its automotive-grade AEC-Q100 qualification, programmable spread-spectrum modulation for EMI reduction, I²C configuration interface, and operation over –40 °C to +125 °C ambient temperature range.

Technical Context

The CY24271ZXCT implements a fractional-N PLL architecture with a 25 MHz crystal reference input and configurable feedback dividers to generate precise output clocks. Its internal voltage-controlled oscillator (VCO) operates between 1.2 GHz and 2.4 GHz, enabling fine frequency resolution down to 1 Hz steps via I²C register writes.

All three LVCMOS outputs support independent enable/disable control, slew-rate adjustment, and phase offset programming. The device includes built-in power-on reset logic, lock detection flag, and fail-safe mode that forces outputs to logic low upon PLL unlock or supply fault.

Key Specifications

Pinout & Package

Supplied in a 24-pin TSSOP package (7.8 mm × 4.4 mm, 0.65 mm pitch) with exposed thermal pad for enhanced heat dissipation in high-reliability applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable clock generator applications.

Compared with Si5341-B-GM and CDCE925PW, the CY24271ZXCT uniquely combines AEC-Q100 Grade 0 operation, integrated fail-safe behavior, and programmable spread-spectrum-making it the only option qualified for safety-critical automotive timing without external supervision circuitry.

Availability

CY24271ZXCT is available at Aetrix Electronics and suitable for engine control units, ADAS domain controllers, industrial PLC CPU modules, and automotive body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY24271ZXCT 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 semiconductors, microcontrollers, sensors, and automotive ICs, with global R&D and manufacturing infrastructure.

The CY24271ZXCT belongs to Infineon's CYPRESS™ Clock Generators product line, engineered specifically for deterministic, low-jitter, and AEC-Q100-compliant timing in automotive powertrain and chassis systems.

FAQ

What is the maximum allowable load capacitance on each CLKOUT pin?

Each CLKOUT pin supports up to 15 pF total capacitive load, including PCB trace capacitance and receiver input capacitance. Exceeding this limit increases rise/fall time and may cause setup/hold violations at downstream devices. For loads >10 pF, slew-rate control bits should be set to "slow" to maintain signal integrity and reduce EMI.

Does CY24271ZXCT support dynamic frequency switching during operation?

Yes-the device supports real-time frequency changes via I²C writes to the PLL divider registers without requiring reset or clock interruption. Switching occurs synchronously on the next VCO cycle, resulting in glitch-free transitions with bounded phase error (<±10°). All outputs update simultaneously, preserving inter-channel phase relationships.

How is the fail-safe mode triggered and what happens to the outputs?

Fail-safe mode activates when either PLL unlock is detected (via internal lock detector) or VDDCORE drops below 1.62 V. In response, all three CLKOUT pins are forced to logic low within 200 ns, OE pins are ignored, and the I²C interface enters high-impedance state. This behavior is hardware-implemented and requires no firmware intervention.

Can the spread-spectrum modulation be disabled after initial configuration?

Yes-SSM can be enabled or disabled at any time via the SSM_EN bit (register 0x0E, bit 7). Disabling SSM restores nominal center frequency with no transient disturbance. The modulation depth and frequency remain stored in nonvolatile shadow registers and persist across power cycles unless explicitly rewritten.