A digital-to-analog converter is disclosed. The converter includes a gradient correction module that generates a correction term based on a model of gradient error. The correction term is then applied to the signal path in the digital domain or applied to the output of the digital-to-analog converter in the analog domain. The model used to generate the correction term is based on a vertical gradient error in the array of current source elements, which may be modelled and calibrated using a second-order polynomial. Further, a digital-to-analog converter having a Nyquist DAC and an oversampled DAC is disclosed. When the oversampled DAC is enabled, the resolution of the Nyquist DAC may be increased while slowing the conversion rate.