SI32291-A-GM

Telecom Overview

The Skyworks Solutions Inc. SI32291-A-GM is a wideband dual Foreign Exchange Station (FXS) interface device operating from a 3.3 V supply. It integrates two complete telephony channels within an 8 x 8 mm 68-pin QFN package, supporting industrial temperature ranges from -40 °C to +85 °C. The component features a 3-wire Integrated Serial Interface (ISI) and includes built-in DTMF detection capabilities. It supports battery voltages up to -140 V and incorporates programmable DC-DC converter controllers for optimized power efficiency.

Telecom Feature Summary

• Performs all BORSCHT functions including battery feed, over-voltage protection, ringing supervision, codec processing, hybrid generation, and test capabilities.
• Supports wideband audio transmission and reception with integrated DSP for metallic loop testing and self-diagnostic routines.
• Integrates flexible tracking DC-DC controllers compatible with low-cost capacitive ultra-boost configurations to minimize heat generation.
• Enables software-programmable parameters for ringing frequency, amplitude, cadence, AC impedance synthesis, and transhybrid balance.

Telecom Applications

• VoIP gateways and routers
• xDSL Integrated Access Devices (IADs)
• Analog Terminal Adapters (ATA)
• Wireless Fixed Terminals (WFT)
• Private Branch Exchange (PBX) systems

Telecom Procurement Notes

Verify the specific suffix 'G' confirms the industrial temperature grade (-40 °C to +85 °C) rather than the commercial 'F' grade. Confirm the ISI interface requirement matches the host system, as PCM/SPI variants exist within the same family. Ensure the ordering documentation specifies the tray shipping option, as tape and reel availability requires an 'R' suffix designation.

Telecom Selection Notes

Select this model when dual FXS channels are required alongside DTMF detection functionality. The G-grade variant is necessary for deployments in environments exceeding standard commercial temperature limits. Verify that the host processor supports the 3-wire ISI protocol or configure the system to utilize the SPI mode if supported by the specific hardware revision.

Telecom Part Context

This component belongs to the Si3229x ProSLIC series, which provides single-chip solutions for analog telephony interfaces. The Si32291-A-GM specifically differentiates itself by combining dual channel support with DTMF detection capabilities, distinguishing it from the Si32290 which lacks this feature. It serves as a core interface element for converting analog voice signals to digital formats for network transport.

Telecom Replacement Considerations

The Si32291-A-FM is the direct functional equivalent but operates within the commercial temperature range (0 °C to 70 °C). For applications requiring PCM interfaces instead of ISI, consider the Si32293-A-GM, which adds daisy-chain mode support while retaining DTMF detection.