SI32175-C-FM1

Telecom Overview

The SI32175-C-FM1 is a single-channel ProSLIC FXS interface IC designed for telephony applications. It utilizes the proprietary three-wire Integrated Serial Interface (ISI) to connect with System-on-Chips, supporting both PCM and SPI protocols within this bus. The device operates on a 3.3 V supply voltage ranging from 3.13 V to 3.47 V and features a maximum battery voltage rating of -110 V. It supports wideband voice transmission and includes DTMF detection capabilities. The component functions within an ambient temperature range of 0 °C to 70 °C and is housed in a 42-pin QFN package measuring 5x7 mm.

Telecom Feature Summary

• Integrates complete FXS solution performing all BORSCHT functions
• Features proprietary ISI digital interface combining PCM, SPI, and interrupt data
• Includes internal balanced or unbalanced ringing generator with patented low power operation
• Supports software-programmable parameters including AC impedance and DC current loop feed

Telecom Applications

• Customer Premise Equipment (CPE)
• VoIP DSL Gateways and Routers
• Wireless Local Loop (WLL)
• Integrated Access Devices (IAD)

Telecom Procurement Notes

Verify the specific suffix FM1 indicates the F-grade temperature rating of 0 to 70 °C rather than the G-grade variant. Confirm ISI interface compatibility with the target SoC before integration. Ensure the design accommodates the 42-pin QFN thermal requirements and verify that the -110 V battery voltage rating aligns with the intended line state specifications.

Telecom Selection Notes

Select the SI32175-C-FM1 when a three-wire ISI interface is required instead of standard PCM/SPI. This model provides DTMF detection functionality unlike the Si32172/3/6/7 variants. Choose this part over the G-grade version if the application environment remains within the 0 to 70 °C operating range. Verify that the -110 V battery voltage limit meets the specific loop length and ringing voltage requirements.

Telecom Part Context

This component belongs to the Si3217x-C family of ProSLIC products manufactured by Silicon Laboratories. These devices are pin-compatible single-channel solutions implementing foreign exchange station interfaces. The family includes variants with either PCM/SPI or ISI interfaces and different voltage ratings. The SI32175 specifically bridges the gap between complex DSP connections and analog line requirements using the integrated serial interface.

Telecom Replacement Considerations

The SI32175-C-GM1 serves as a direct replacement offering extended temperature support from -40 °C to 85 °C while maintaining identical electrical characteristics and interface protocols.