Methods, systems, and apparatuses for calibration of analog to digital converters (ADC) are described herein. In an aspect, an ADC includes a plurality of slices. Each slice includes a digital to analog converter (DAC), a comparator, and a digital processing unit (DPU). The digital processing unit is electrically connected to the comparator and the DAC. In another aspect, an analog-to-digital converter includes an input module and an analog to digital converter core configured to receive an analog input from the input module and generate a digital output. The ADC is configured to adjust a precision of the analog to digital converter core based on a quality of the analog input signal.