The invention provides a digital-to-analog converter (DAC) circuit. The DAC circuit includes a first circuit configured to receive a first portion of the digital signal and generate a first output voltage at a level selected from a first plurality of levels where at least two adjacent voltage levels have a first potential difference. The DAC circuit further includes a second circuit configured toreceive a second portion of the digital signal and generate a second output voltage at a level selected from a second plurality of levels where at least two adjacent voltage levels have a second potential difference and the second circuit includes a compensation circuit configured to adjust the second potential difference such that the second potential difference is an integer multiple of the first potential difference. The DAC circuit also comprises an output node which is coupled to the first circuit and the second circuit so as to provide simulation signals. According to the invention, by using the compensation circuit to adjust the relation of the potential difference, linear simulation output can be provided.