Patent ID: 11451240

Abstract:
A quad signal generator circuit generates four 2N-1 bit control signals in response to a 2N-1 bit thermometer coded signal. A digital-to-analog converter (DAC) circuit has 2N-1 unit DAC elements, with each unit DAC element including four switching circuits controlled by corresponding bits of the four 2N-1 bit control signals. Outputs of the 2N-1 unit DAC elements are summed to generate an analog output signal. The quad signal generator circuit controls a time delay applied to clock signals relative to the 2N-1 bit thermometer coded signal and a time delay applied to the 2N-1 bit thermometer coded signal relative to the delayed clock signals in logically generating the four 2N-1 bit control signals. The analog output signal may be a feedback signal in a sigma-delta analog-to-digital converter (ADC) circuit that includes a multi-bit quantization circuit operating to quantize a filtered loop signal to generate the 2N-1 bit thermometer coded signal.