73M1866B-IMR/F

Overview

The 73M1866B-IMR/F is a MicroDAA™ integrated circuit designed for Foreign-Exchange-Office (FXO) applications in Voice-over-IP (VoIP) systems. It integrates the complete Data Access Arrangement (DAA) function into a single package, enabling direct connection of PCM formatted voice channels to the Public Switched Telephone Network (PSTN). The device operates on a 3.0 V to 3.6 V supply and supports industrial temperatures from -40°C to +85°C. It features an SPI control interface with daisy-chain capability and a PCM highway interface supporting E-1/T-1 formats. The component utilizes a patented pulse transformer isolation barrier rated up to 6 kV.

Feature Summary

• Patented MicroDAA technology providing full DAA functionality within a single silicon package.
• Integrated digital isolation barrier using a small pulse transformer for reliable power and data transfer.
• Configurable analog gain stages allowing adjustment of transmit and receive signal paths.
• Supports global compliance standards including FCC, ETSI, and JATE requirements.

Applications

• Voice-over-IP (VoIP) equipment requiring PSTN connectivity
• Computer Telephony Integration (CTI) systems
• PBX systems and Internet appliances
• Voicemail systems and POTS termination equipment

Procurement Notes

Verify the specific ordering suffix against current manufacturer documentation, as the 73M1866B family has undergone discontinuation notices. Confirm that the IMR/F suffix corresponds to the correct 42-pin QFN package variant intended for your design. Ensure compatibility with existing firmware configurations regarding the SPI and PCM interfaces before finalizing procurement plans.

Selection Notes

Select this component when a compact, single-package solution for FXO VoIP applications is required. It is suitable for designs needing high integration levels to reduce bill-of-materials count. Consider the 42-QFN package dimensions for PCB layout constraints. Verify that the system architecture can support the required SPI and PCM highway timing specifications for master or slave modes.

Part Context

This part belongs to the Teridian Semiconductor MicroDAA family, now managed by Analog Devices Inc./Maxim Integrated. It serves as a consolidated alternative to traditional multi-component DAA designs. The device simplifies system integration by combining line-side protection, hybrid circuits, and codec interfaces into one unit, reducing board space and assembly complexity for telecom manufacturers.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. The datasheet indicates a Product Change Notification (PCN) for End-of-Life (EOL) status dated May 2, 2016. Designers should consult official distributor archives or engineering change notices for legacy replacement strategies.