An analog-to-digital converter (ADC) circuit includes a first comparator circuit, a second comparator circuit, and an interpolation circuit. The first comparator circuit includes a first input terminal to receive a first reference voltage signal and a second input terminal to receive an input voltage signal. The second comparator circuit includes a first input terminal to receive a second reference voltage signal and a second input terminal to receive the input voltage signal. The interpolation circuit includes a first input terminal coupled to a first output terminal of the first comparator and a second input terminal coupled to a first output terminal of the second comparator.