An N-bit DAC comprises a main DAC circuit having main nodes on which analogue voltages are produced of progressively increasing values in steps of the value of one MSB value, and a sub-DAC circuit having secondary nodes on which analogue voltages are produced of progressively increasing values in steps of the value of one LSB. A main switch network couples the secondary nodes to a selected pair of main nodes as the MSB value of the digital input signal varies. A secondary switch network selectively couples one of secondary nodes to an output terminal for providing an analogue voltage output signal. The main nodes are coupled between main terminals, and a voltage reference is applied across input terminals. A first offset circuit and a first compensating circuit are selectively coupleable between the main DAC circuit and the input terminals for offsetting the main node analogue voltages downwardly.