Digital gain control for sound mixer, etc. - has D=A converter producing analog control signal for amplifier from digital control signal and filter to remove switching transients

摘要

The digital control, e.g. for altering gain in a sound mixer, converts the digital control signals (1) into analog signals using a D/A converter (3). The D/A converter's output is filtered and applied to the analog control input of the amplifier (7). The analog control signal applied to the amplifier continuously follows any change in the digital control voltage. The gain, or other variable, may be made linearly dependent on the analog control signal by incorporating a circuit with logarithmic characteristics.