Patent ID: 8896476

Claim:
A successive operation register (SAR) analog-to-digital converter (ADC) circuit comprising: a voltage comparator having a first analog signal input, a second analog input, and a decision output; a decision logic circuit having an input connected to the decision output of the voltage comparator and a digital output; a digital-to-analog converter (DAC) having a digital input connected to the digital output of the decision logic circuit and an analog output connected to the second analog input of the voltage comparator; further comprising: a bit reliability circuit that detects a delay time of the voltage comparator and, if the detected delay time is greater than a delay threshold time τ MV , outputs a bit reliability decision signal; a digital noise reduction circuit that is selectively activated if the bit reliability decision signal indicates the detected delay time is greater than the delay threshold time τ MV and produces a noise-reduced decision output that supersedes the decision output of the voltage comparator.