Introduction
The Agere Systems Inc. L9215 is a subscriber line interface circuit that is optimized for short-loop, power-sensitive 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
■ Onboard ringing generation
■ Three ringing input options:
    — Sine wave
    — PWM
    — Logic level square wave
■ Flexible VCC options:
    — 5 V or 3.3 V VCC
    — No –5 V required
■ Battery switch to minimize off-hook power
■ 11 operating states:
    — Scan mode for minimal power dissipation
    — Forward and reverse battery active
    — On-hook transmission states
    — Meter pulse states
    — Ring mode
    — Disconnect mode
■ Ultralow on-hook power:
    — 27 mW scan mode
    — 42 mW active mode
■ Two SLIC gain options to minimal external components in codec interface
■ Loop start, ring trip, and ground key detectors
■ Software- or hardware-controllable current-limit and overhead voltage
■ Meter pulse compatible
■ 32-pin PLCC package
■ 48-pin MLCC package

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