General Description

The 73M1903 is a single-chip analog front end (AFE) that’s ideal for DSP or RISC-based soft modem applications such as fax and multi-function peripherals (MFPs), game consoles, Internet appliances, and set-top boxes. It offers a complete array of features designed to reduce the external component count. The design of the 73M1903 digital interface is compatible with the serial ports found on most commercially available DSPs. It includes a similar CODEC to those found on other high performance analog front ends as well as additional support for applications where AFEs are used in the design of a modem (MAFE). The 73M1903 utilizes a serial data port for exchange of payload and control information with a host processor (or DSP).

The 73M1903 includes fully differential hybrid driver outputs, which connect to the telephone line interface through a transformer-based DAA. The receive pins are also fully differential for maximum flexibility and performance. This arrangement allows for the design of a high performance hybrid circuit to improve signal to noise performance under low receive level conditions, and compatibility with any standard transformer intended for PSTN communications applications.


  • Single chip Analog Front End for up to V.92
  •  Programmable sample rates
  • Operates with reference clock range of 9-40MHz
  • Host synchronous serial interface operation
  • Pin compatible with 73M2901CL single chip modem (32-TQFP package option)
  • Low power modes
  • On board line interface drivers
  • Full differential receiver/transmitter
  • Direct interface to transformer
  • 3.0V – 3.6V operation
  • Industrial temperature range
  • TQFP 32 and QFN 32