A digital-to-analog converter (DAC) device includes a current-steering DAC circuitry and a calibration circuitry. The current-steering DAC circuitry generates a first signal according to multiple least significant bits of an input signal, and generates a second signal according to multiple most significant bits of the input signal. The calibration circuitry performs a non-binary search algorithm to generate a calibration signal in response to a comparison result of the first signal and the second signal, in order to calibrate the current-steering DAC circuitry according to the calibration signal.