This paper presents a 13-bit fully-differential successive approximation register analog-to-digital converter with a hybrid DAC that is suitable for sensor applications. An innovative dithering plus averaging technique is developed around this originally-designed 10-bit ADC to make it possible to attain an effective resolution of 13 bits in a configurable fashion without calibration. The ADC has a nominal 13-bit sampling rate of 5.5 kS/s suitable for many sensor applications. It operates with a multiple supply voltage from 0.9 V to 0.6V.