A 16 bit + sign monotonic precise current DAC for sensor applications working in a harsh environment is described. It is working in a wide temperature range with high output voltage swing and low current consumption.

The converter is based on current division and segmentation techniques to guarantee monotonicity. Two active cascoding loops and one follower loop are used to improve the output impedance, the accuracy and the voltage compliance of the DAC. The resolution of the DAC is further increased by applying PWM to one fine LSB current. To achieve low power consumption unused coarse current sources are switched off. Several second order technological effects influencing final performance and circuits dealing with them are discussed.