LE79R79-1DJCT

Telecom Overview

The LE79R79-1DJCT is a Ringing Subscriber Line Interface Circuit (SLIC) manufactured by Microchip Technology, originally developed by Zarlink Semiconductor. It is housed in a 32-pin PLCC package and supports commercial temperature ranges from 0 to 70°C. The device integrates on-chip ringing generation capable of meeting LSSGR five-ringer equivalent specifications with trapezoidal waveforms. Key electrical parameters include a VBAT1 range of -40.5 to -75 V and a VBAT2 range of -19 V to VBAT1. It features a current gain of 1000, longitudinal balance of 52 dB, and an internal VEE regulator that eliminates the need for external negative power supplies.

Telecom Feature Summary

• Integrates on-chip ringing function with trapezoidal waveform generation using CMOS-compatible inputs
• Supports dual battery operation with automatic switching between high voltage for open-circuit requirements and low voltage for power conservation
• Includes programmable constant-current feed, loop-detect threshold, and polarity reversal options
• Features ground-key detection and two on-chip relay drivers for external relay control

Telecom Applications

• ISDN terminal adaptors and fixed radio access systems
• Integrated Access Devices (IADs) and Network Interface Units (NIUs)
• DSL modems, cable modems, and set-top boxes
• Voice over ISDN or T1/E1 interfaces and intelligent PBX systems
• Wireless Local Loop (WLL), APON, FITL, and NGN short-loop CPE applications

Telecom Procurement Notes

Verify the specific ordering suffix 'T' if tape and reel packaging is required, as standard tubes are listed for the base part number. Confirm the manufacturer origin, noting that Zarlink assets were acquired by Microchip Technology. Ensure compatibility with lead-free assembly processes, as the green package meets RoHS Directive 2002/95/EC standards. Cross-reference datasheet revision O version 2 for accurate pin descriptions and electrical characteristics.

Telecom Selection Notes

Select the LE79R79-1DJCT for short-loop telephony applications requiring integrated ringing without external components. The '-1' suffix indicates 52 dB longitudinal balance with polarity reversal capability. Consider the 32-pin PLCC package for through-hole mounting requirements. Evaluate thermal performance constraints, as junction temperatures above 145°C may degrade reliability. Verify that the application environment falls within the specified commercial temperature range of 0 to 70°C.

Telecom Part Context

This component belongs to the Le79R79 family of bipolar monolithic SLIC devices designed for cost reduction in system-level designs. It addresses major telephony markets including central office, private branch exchange, and digital loop carrier applications. The device minimizes component count by integrating BORSHT functions, supporting automated manufacturing and conserving board space compared to discrete solutions.

Telecom Replacement Considerations

Parts marked with the 'Am' prefix are equivalent to those with the 'Le' prefix in form, fit, and function. The only difference is the topside marking prefix. No other direct substitute part numbers are documented in the provided source material.