73M1866B-IM/F

Overview

The 73M1866B is a single-package silicon Data Access Arrangement (DAA) designed for Foreign-Exchange-Office (FXO) Voice-over-IP applications. It connects PCM formatted voice channels to the PSTN via a two-wire twisted pair interface. 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 8-kHz sampling rate with ITU-T G.711 compliant μ-law and A-law companding, plus a 16-bit linear mode at 16 kHz. Transmit and receive digital gains are adjustable from –18 dB to +7.375 dB in 0.125 dB increments. The component includes a PCM highway interface with automatic clock detection, SPI control, and isolation up to 6 kV.

Feature Summary

• Patented MicroDAA technology providing integrated DAA functionality within a single package for simplified system integration.
• Digital isolation barrier using a small pulse transformer to transfer power and data across the barrier for reliable EMI tolerance.
• Configurable analog gain capabilities allowing up to +6 dB line-side transmit gain and +3 dB receive signal path gain.
• Comprehensive line sensing and status monitoring including ring detection, polarity reversal, and call progress monitoring.

Applications

• VoIP equipment requiring connectivity to the PSTN for emergency service calling.
• Computer telephony systems and PBX networks.
• Internet appliances and Voicemail systems.
• POTS termination equipment.

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation to confirm package type and temperature range. Note that this component may be subject to End-of-Life notices or product changes; consult official distributor resources for availability status and alternative sourcing options before finalizing procurement plans.

Selection Notes

Select the 73M1866B when a single-chip solution for FXO VoIP interfaces is required to minimize board space. Ensure the design accommodates the 3.0 V to 3.6 V operating voltage and utilizes the appropriate PCM highway interface timing. Consider the 42-pin QFN package dimensions if high-density layout is necessary for the application.

Part Context

This component belongs to the Teridian MicroDAA family, which includes the 73M1966B series. While the 73M1966B separates functions into Host-Side (73M1906B) and Line-Side (73M1916) devices, the 73M1866B integrates these functions into one package. It serves as a direct interface between digital PCM networks and analog telephone lines.

Replacement Considerations

Public confirmed substitute part numbers: 73M1966B (requires split host/line design).