LE79R241DJC

Telecom Overview

The LE79R241DJC is a high-voltage bipolar Intelligent Subscriber Line Interface Circuit (ISLIC) manufactured by Zarlink Semiconductor, now part of Microchip Technology. It serves as the line driver and sensing component within the VE790 series voice chipset, designed to operate exclusively with VE790 series ISLAC devices. The device implements BORSCHT functions including DC feed, ringing, signaling, and hybrid circuits. It supports internal or external ringing generation and provides comprehensive subscriber line diagnostics such as leakage resistance, loop resistance, and capacitance measurement. The LE79R241DJC variant specifically utilizes a 32-pin Green PLCC package compliant with RoHS directives.

Telecom Feature Summary

• Intelligent thermal management system that offloads excess power dissipation to external resistors to maintain safe junction temperatures.
• Integrated self-test and line-test capabilities for remote fault resolution without dedicated external test hardware.
• Supports both internal and external ringing configurations with synchronized relay operation.
• Programmable DC feed characteristics independent of battery voltage, featuring current limiting and selectable thresholds.

Telecom Applications

• Cost-effective voice solutions for long or short loop applications providing POTS and integrated test capabilities.
• PBX and Key Telephone Systems (KTS) requiring software-configurable line interface functions.
• Pair Gain systems utilizing the VE790 series chipset for multi-channel architecture.

Telecom Procurement Notes

Verify the ordering suffix 'DJC' corresponds to the 32-pin PLCC Green package when sourcing replacements. Confirm compatibility with the specific VE790 series ISLAC codec intended for the design. Ensure the supplier adheres to lead-free assembly processes compatible with the green package's matte-tin plating requirements.

Telecom Selection Notes

Select the LE79R241DJC when a RoHS-compliant plastic leaded chip carrier package is required for the VE790 series application. This model is distinct from the standard non-green PLCC version and the QFN tray-packaged variant. Ensure the design accommodates the necessary external thermal management resistors connected to TMP, TMN, and TMS pins for optimal power handling.

Telecom Part Context

This component belongs to the Zarlink VE790 series voice chipset family, which integrates all subscriber line interface functions. The LE79R241 acts as the high-voltage bipolar interface unit, while the companion VE790 series ISLAC devices provide low-voltage CMOS conversion, control, and DSP functions. Together they form a complete software-programmable solution for worldwide line card requirements.

Telecom Replacement Considerations

The LE79R241JC is the standard non-green equivalent in the same 32-pin PLCC package. For surface-mount applications requiring a smaller footprint, the LE79R241QC in a 32-pin QFN package serves as an alternative, though it requires different board layout considerations for the exposed thermal pad.