843242AGLFT

Specialized ICS Overview

The Renesas 843242AGLFT is a FemtoClock LVPECL frequency synthesizer designed for Ethernet reference clock generation. It features two differential LVPECL output pairs and operates on a single 3.3V supply. The device generates frequencies of 625MHz, 312.5MHz, 156.25MHz, or 125MHz using a 31.25MHz or 26.041666MHz crystal input. It achieves typical RMS phase jitter as low as 0.4ps at 625MHz. Packaged in a 16-TSSOP (4.40mm width) surface-mount case, it supports an operating temperature range of 0°C to 70°C.

Specialized ICS Feature Summary

• Two independent differential LVPECL output banks with selectable division ratios
• Low phase noise performance with typical RMS jitter of 0.4ps at 625MHz
• Supports 31.25MHz or 26.041666MHz parallel resonant crystals
• Configurable via SELA/SELB pins for four distinct output frequencies

Specialized ICS Applications

• Ethernet reference clock generation
• High-speed serial data transmission systems
• Network infrastructure equipment requiring precise timing

Specialized ICS Procurement Notes

Verify the 'T' suffix indicates Tape & Reel packaging versus 'LF' Tube packaging. Confirm RoHS 6 compliance status. Check for End-of-Life notices as IDT products transition to Renesas. Ensure the specific ordering code matches the required package quantity and lead-free specifications.

Specialized ICS Selection Notes

Select this component when dual independent LVPECL outputs are required for Ethernet applications. Verify that the system can accommodate 31.25MHz or 26.041666MHz crystals. Ensure the 0°C to 70°C commercial temperature range meets environmental requirements. Consider power dissipation calculations if multiple outputs are loaded simultaneously.

Specialized ICS Part Context

This part belongs to the FemtoClock family of crystal-to-LVPECL synthesizers. Originally manufactured by Integrated Device Technology (IDT), it was acquired by Renesas Electronics. The 843242 series utilizes third-generation low phase noise VCO technology to meet stringent Ethernet jitter standards while maintaining a compact 16-pin TSSOP footprint.

Specialized ICS Replacement Considerations

Public confirmed substitute part numbers: None identified in verified documentation.