Digital automatic gain control for hearing aids

A new digital method for implementing Automatic Gain Control (AGC) in a hearing aid is described. The AGC characteristics are programmable, which allows the system to be customized for a particular user. Since no external timing components are required the implementation is area-efficient, completely monolithic, and insensitive to temperature variation and component aging. The technique may be applied to both input and output compression systems. Simulation results are presented.