251MI-39LF

Overview

The 251MI-39LF is a field-programmable VersaClock synthesizer manufactured by Renesas Electronics Corporation. It operates as a single-output clock generator and frequency synthesizer designed to replace multiple discrete crystals and oscillators. The device utilizes Phase-Locked Loop (PLL) techniques to generate output frequencies up to 200 MHz from input sources ranging from 3 to 150 MHz. It features configurable spread spectrum modulation for electromagnetic interference reduction and includes four addressable configuration registers for flexibility. The component supports operation with standard fundamental mode crystals or external clock inputs, offering controllable drive levels and low-power CMOS processing within an 8-pin SOIC package.

Feature Summary

• Field programmability via One-Time Programmable ROM allows customization without factory reprogramming.
• Configurable spread spectrum modulation reduces system electromagnetic interference emissions.
• Integrates PLL technology to replace multiple discrete crystal oscillators on the board.
• Supports power-down functionality that tri-states outputs and disables internal PLLs.

Applications

• General-purpose clock generation in embedded systems
• Electromagnetic interference reduction in high-speed digital circuits
• Replacing fixed-frequency oscillators in space-constrained designs

Procurement Notes

Verify the specific suffix '39' against official Renesas documentation to confirm pinout and electrical characteristics, as suffixes often denote specific packaging or temperature grades. Confirm RoHS compliance status through current datasheets. Check for end-of-life notices or obsolescence warnings prior to procurement. Ensure programming tools are available if field programmability is required.

Selection Notes

Select this component when a single programmable source can replace multiple fixed-frequency oscillators to save board space. Consider its 200 MHz maximum output capability and 3-150 MHz input range compatibility. Evaluate the need for spread spectrum features for EMI compliance. Verify voltage supply requirements match the target system's 3.3V logic levels.

Part Context

This part belongs to the VersaClock family of programmable clock synthesizers. It is functionally related to other models like the 251PMILF but may differ in specific configuration options or manufacturing revisions. The product line focuses on providing flexible clock solutions using PLL technology to simplify system design and reduce component count.

Replacement Considerations

Public confirmed substitute part numbers: None identified in provided data.