LE79R79-2DJCT

Telecom Overview

The LE79R79-2DJCT is a Ringing Subscriber Line Interface Circuit (SLIC) from the VE580 series, manufactured by Microchip Technology. It integrates on-chip ringing and battery switching for short-loop applications. The device operates with VBAT1 ranging from -40.5 to -75 V and VBAT2 from -19 V to VBAT1. It provides a longitudinal balance of 63 dB with polarity reversal support. Key electrical parameters include a current gain of 1000, an open-circuit voltage up to 88 V, and a ringing voltage of 69 Vpk. The component is housed in a 32-pin PLCC package.

Telecom Feature Summary

• Integrates trapezoidal ringing generation and ring-trip detection on-chip
• Features internal battery switching between two supply voltages for power optimization
• Supports programmable constant-current feed and loop-detect thresholds
• Includes dual relay drivers and ground-key detector functionality

Telecom Applications

• ISDN Terminal Adaptors (TA)
• Integrated Access Devices (IADs)
• Network Interface Units (NIUs)
• Cable and DSL Modems
• Voice over ISDN or T1/E1 systems

Telecom Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and performance grade. The 'T' suffix indicates tape and reel packing, while its absence typically denotes tube packaging. Ensure compatibility with lead-free assembly processes as specified in the datasheet revision history.

Telecom Selection Notes

Select this model for short-loop telephony applications requiring integrated ringing capabilities. The -2 suffix specifies a 63 dB longitudinal balance with polarity reversal, suitable for stringent line card requirements. Consider the thermal performance of the 32-pin PLCC package and ensure adequate heat dissipation for continuous operation within the specified temperature ranges.

Telecom Part Context

This component belongs to the Zarlink/Le79R79 family of subscriber line interface circuits, originally developed by Zarlink Semiconductor Inc. and now distributed by Microchip Technology. The VE580 series addresses central office, PBX, and digital loop carrier markets by minimizing external component counts through high integration of BORSHT functions.

Telecom Replacement Considerations

Parts marked with the "Am" prefix are equivalent in form, fit, and function to those with the "Le" prefix. Other devices in the Le79R70/79/100/101 series may offer similar features but require verification of specific performance grades and pinout compatibility.