Incremental analog to digital converter incorporating noise shaping and residual error quantization

A method, comprising:

• in response to receiving a reset signal, filtering, by a loop filter, an analog input signal, resulting in a filtered analog input signal;
• applying a first reference voltage to a successive approximation register (SAR) quantizer;
• converting, by the SAR quantizer based on the first reference voltage, the filtered analog input signal to a first intermediate digital output, wherein the converting of the filtered analog input signal comprises shaping, by a feedback loop associated with the SAR quantizer, quantization noise associated with the converting of the filtered analog input signal, and wherein the first intermediate digital output has a first resolution;
• generating, by a digital filter, a digital output signal by digitally filtering the first intermediate digital output, wherein the digital output signal has a second resolution that is greater than the first resolution;
• converting, by a digital to analog converter, the first intermediate digital output to a converted analog signal;
• subtracting, by a differential amplifier, the converted analog signal from the analog input signal, resulting in a residual analog input signal;
• applying a second reference voltage to the SAR quantizer instead of the first reference voltage in response to the subtracting, wherein the second reference voltage is lower than the first reference voltage;
• and
• converting, by the SAR quantizer based on the second reference voltage, the residual analog input signal to a second intermediate digital output.