An analog front end chip for V.32 modems

The design and construction of a complete high-speed modem front end on a single combined analog/digital application-specific integrated circuit are described. The chip is part of a highly integrated modem core created specifically for a family of V.32-based products. It incorporates all of the necessary analog/digital conversion, filtering, and gain control functions. Also included is an adaptive analog echo canceler designed to enhance system performance and reduce circuit complexity in other areas of the chip