US Patent 7215267 Analog-to-digital converter with dither control

An analog-to-digital converter system comprises an analog-to-digital converter and a dither generator. The analog-to-digital converter receives an analog input signal and generates a digital signal that is proportional to the analog input signal. The output of the analog-to-digital converter is dominated by quantization error. The dither generator is responsive to a user-controlled input for generating an output signal. An adder sums the digital signal from the analog-to-digital converter with the output signal from the dither generator to provide a summed signal. The summed signal is either dominated by quantization noise or is properly dithered depending upon the user-controlled input.