Introduction
The Agere Systems Inc. L9214 is a subscriber line interface circuit that is optimized to provide a very low-cost solution for short- and medium-loop applications. This device provides the complete set of line interface functionality, including power ringing needed to interface to a subscriber loop. This device has the capability to operate with a VCC supply of 3.3 V or 5 V and is designed to minimize external components required at all device interfaces.

Features
■ Low-cost solution
■ Onboard ringing generation with software adjustable crest factor switching
■ Flexible VCC options:
    — 3.3 V or 5 V VCC
    — No –5 V required
■ Power control options:
    — Power control resistor
    — Automatic battery switch to minimize off-hook power
■ Eight operating states:
    — Scan mode for minimal power dissipation
    — Forward and reverse battery active
    — On-hook transmission states
    — Ring mode
    — Disconnect mode
■ Low on-hook power:
    — 25 mW scan mode
    — 165 mW active mode
■ Two SLIC gain options to minimize external components in codec interface
■ Loop start, ring trip, and ground key detectors
■ Programmable current limit
■ On-hook and scan mode line voltage clamp
■ Thermal protection
■ 48-pin MLCC, 32-pin PLCC, and 28-pin SOG (Please contact your Agere Sales Representative for availability) packages

Applications
■ Voice over Internet Protocol (VoIP)
■ Cable Modems
■ Terminal Adapters (TA)
■ Wireless Local Loop (WLL)
■ Telcordia Technologies™ GR-909 Access
■ Network Termination (NT)
■ PBX
■ Key Systems