The IA3120/21 are single chip, embedded modem analog front end ICs designed specifically for soft modem applications such as set top boxes, that require a low cost, full-featured discrete DAA solution to satisfy the spectrum of global telecom regulations compliance standards (FCC68, CTR21, JATE, and AUSTEL).

The IA3120/21 are designed to implement modems up to V.92 (56kbps) in systems where the modulation software function is performed by the main processor (Pentium, RISC, DSP, etc.). The IA3120/21 include a 4-signal serial digital interface (compatible with the set top box industry-standard STLC7550 for easy design-in) and a connection to the telephone line by means of a transformer-based, discrete DAA. To further ease the design-in of the part, the IA3120/21 include a number of features that promote maximum flexibility for the application designer—on chip hybrid allowing for direct connection to standard transformers, on/off hook control, programmable sampling rates to support various data and voice modulation standards, a flexible master clock generation to accommodate a range of frequencies or clock inputs, including 27MHz, support for master or slave modes of operation1, including dual codec support, and multiple programmable, general purpose I/O pins. In addition to these features, the IA3120/21 are also designed to anticipate the other important priorities of embedded modem OEMs, such as reduced cost, and the preservation of valuable PCB real estate.

Note 1: Only the IA3121 includes slave mode support and analog speaker outputs.