SI32178-B-FM1R

Telecom Overview

The SI32178-B-FM1R is a single-channel ProSLIC FXS telephony interface IC from the Si3217x family, manufactured by Silicon Laboratories. It operates on a 3.3 V supply and supports PCM/SPI digital interfaces. The device performs all BORSCHT functions with a maximum battery voltage of -110 V and an operating temperature range of 0 to 70 °C. Key electrical specifications include a DC differential output resistance of 160 to 640 Ω, idle channel noise of 8 to 12 dBrnC (C-message weighted), and PSRR of 55 dB. It features wideband voice support, DTMF detection, and integrated DC-DC control.

Telecom Feature Summary

• Performs complete BORSCHT functions for FXS telephony applications
• Supports global programmability via ProSLIC API
• Integrates patented low-power ringing generation
• Includes wideband voice codec and DTMF detection

Telecom Applications

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

Telecom Procurement Notes

Verify component authenticity through authorized distributors or direct manufacturer channels. Confirm the specific suffix FM1R matches the required reel packaging format and RoHS compliance status. Ensure the procurement source provides valid traceability documentation for quality assurance purposes.

Telecom Selection Notes

Select this model for short to medium loop applications requiring FXS functionality with DTMF detection. Verify that the -110 V battery voltage rating aligns with the target network requirements. Ensure the 0 to 70 °C commercial temperature grade meets the environmental constraints of the intended deployment location.

Telecom Part Context

This component belongs to the Si3217x series of pin-compatible ProSLIC products. It is designed to implement complete foreign exchange station solutions compliant with LSSGR, ITU, and ETSI specifications. The series integrates seamlessly with Si3291x FXO devices using capacitive isolation technology.

Telecom Replacement Considerations

The Si32176-B-FM1R serves as a functional substitute within the same family. Both parts share identical pinouts and core FXS capabilities. The primary distinction lies in feature sets; the Si32178 includes DTMF detection while the Si32176 does not.

Telecom FAQ

Does the SI32178-B-FM1R support FXO line-side connectivity?

Yes, the datasheet indicates that this part supports FXO options when connected to Si3291x series devices using patented capacitive isolation technology.

What is the maximum loop resistance supported by this IC?

The device supports a maximum loop resistance of 2000 Ω, calculated as the sum of loop and load resistance at a loop current of 18 mA.

How is the DC differential output resistance defined?

The DC differential output resistance ranges from 160 Ω to 640 Ω under conditions where the loop current is less than the current limit (ILIM).