Analog Devices Inc./Maxim Integrated 73M1906B-IVT/F

Overview

73M1906B-IVT/F from Teridian Semiconductor is a host-side digital interface IC for MicroDAA™ voice-over-IP systems, implementing PCM highway and SPI control for FXO line interfacing. It operates at 3.0–3.6 V, supports 8 kHz/16 kHz sampling, delivers ±6 dB analog gain adjustment, and features ITU-T G.711 µ-law/A-law companding - enabling PSTN connectivity in VoIP gateways and PBX systems.

For engineers reviewing the 73M1906B-IVT/F datasheet, 73M1906B-IVT/F pinout, 73M1906B-IVT/F application, or 73M1906B-IVT/F equivalent, key selection criteria include PCM master/slave mode support, daisy-chain SPI capability (up to 16 devices), industrial temperature range (–40 °C to +85 °C), and compliance with FCC, ETSI ES 203 021-2, and JATE DAA standards.

Technical Context

The 73M1906B-IVT/F functions as the host-side controller in a split-line MicroDAA architecture, communicating digitally with the 73M1916 line-side device across an isolation barrier powered by a small pulse transformer. It handles all digital signal processing, gain control, and protocol management for the PCM highway interface.

It implements automatic clock rate detection on the PCM interface, supports both µ-law and A-law companding per ITU-T G.711, and provides programmable transmit/receive digital gain in 0.125 dB steps from –18 dB to +7.375 dB. Control is performed via a 4-wire SPI interface with daisy-chain support.

Key Specifications

Pinout & Package

73M1906B-IVT/F is available in a 20-pin TSSOP package (5.0 mm × 6.5 mm, 0.65 mm pitch) with exposed thermal pad. Pin assignments are defined per Table 1 of DS_1x66B_001 Rev. 1.6.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DAA host-interface applications.

Compared with Si3217x and SLIC2000, the 73M1906B-IVT/F offers unique advantages in scalable multi-channel VoIP systems where host-side control separation, daisy-chain SPI, and hardware G.711 acceleration reduce firmware load and improve channel density per controller.

Availability

73M1906B-IVT/F is available at Aetrix Electronics and suitable for VoIP gateways, PBX systems, and emergency services terminals requiring stable component supply, long-term lifecycle support, and global regulatory compliance.

Supply support for 73M1906B-IVT/F includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Teridian Semiconductor was a fabless IC designer specializing in highly integrated analog front-ends for voice and energy metering applications before its acquisition by Maxim Integrated in 2011.

The 73M1906B-IVT/F belongs to the MicroDAA™ family, engineered specifically to simplify PSTN interface design in VoIP equipment by integrating DAA control, PCM timing, and regulatory-compliant isolation into a single host-side IC.

FAQ

What is the primary function of the 73M1906B-IVT/F in a MicroDAA system?

The 73M1906B-IVT/F serves as the host-side digital controller in a split-line MicroDAA architecture, managing PCM data exchange, SPI configuration, gain control, and line-event detection for the 73M1916 line-side device. It does not drive the PSTN line directly but coordinates all digital signal processing and interface timing required for compliant FXO operation. The 73M1906B-IVT/F enables full DAA functionality while isolating high-voltage analog circuitry to the companion line-side IC.

Does the 73M1906B-IVT/F support both µ-law and A-law companding?

Yes, the 73M1906B-IVT/F implements hardware-based ITU-T G.711 µ-law and A-law companding, selectable via SPI register configuration. This ensures bit-exact compatibility with North American and European PSTN networks respectively, without requiring host processor intervention or software codec libraries. The 73M1906B-IVT/F performs companding inline during PCM sample conversion, maintaining low-latency voice paths.

Can multiple 73M1906B-IVT/F devices be controlled using a single SPI bus?

Yes, the 73M1906B-IVT/F supports daisy-chain SPI operation, allowing up to 16 devices to share one 4-wire SPI interface (SCLK, MOSI, MISO, CS). Each device forwards unaddressed commands down the chain while responding only to writes targeting its assigned address window. This capability significantly reduces MCU pin count and simplifies layout in multi-port VoIP systems using the 73M1906B-IVT/F.

What package options are available for the 73M1906B-IVT/F?

The 73M1906B-IVT/F is offered exclusively in a 20-pin TSSOP package (5.0 mm × 6.5 mm, 0.65 mm pitch) with exposed thermal pad, as confirmed in Table 1 of DS_1x66B_001 Rev. 1.6. Unlike other members of the 73M1x66B family, the 73M1906B-IVT/F does not have a QFN variant - the -IVT/F suffix denotes this specific TSSOP configuration with industrial temperature and lead-free compliance.

How does the 73M1906B-IVT/F handle clock synchronization with the PCM highway?

The 73M1906B-IVT/F features automatic clock rate detection on the PCM interface, identifying whether the incoming PCM_CLK signal corresponds to 8 kHz or 16 kHz sampling without host intervention. It dynamically configures internal decimation/interpolation filters and timing registers to maintain frame alignment and sample integrity. This eliminates manual clock setup and improves robustness in systems where PCM clock sources may vary across deployments.