251M-33LFT

Overview

The 251M-33LFT is a field-programmable clock synthesizer from the VersaClock family, manufactured by Renesas Electronics Corporation. It operates as a single-output device capable of generating frequencies up to 200 MHz using an internal Phase-Locked Loop (PLL). The component supports Spread Spectrum Clock Generation (SSCG) to reduce electromagnetic interference. It accepts input crystal frequencies between 5 and 27 MHz or clock signals from 3 to 150 MHz. The device utilizes a One-Time Programmable (OTP) ROM for configuration via four addressable registers and functions at a supply voltage of 3.3 V.

Feature Summary

• Field-programmable architecture with OTP ROM and four configurable registers
• Output frequency range from 314 kHz to 200 MHz
• Spread Spectrum Clock Generation (SSCG) capability for EMI reduction
• Input compatibility with crystals (5–27 MHz) or clocks (3–150 MHz)

Applications

• Replacing multiple discrete crystals and oscillators in system designs
• Low-cost clock generation for digital systems requiring spread spectrum modulation
• Applications necessitating controllable output drive levels

Part Context

The 251M-33LFT belongs to the IDT/Renesas VersaClock 251 series of low-cost, single-output clock synthesizers. This series is designed to utilize advanced, low-power CMOS processes and RoHS-compliant packaging. The 'LFT' suffix indicates lead-free construction compliant with environmental standards.

Replacement Considerations

The related part number 251PMILF is listed as obsolete. Designers should verify if the 251M-33LFT serves as a direct functional replacement or consult current Renesas product availability lists for active alternatives within the VersaClock portfolio.