A self-testing and calibration technique for current-steering DACs

Abstract

In this paper, a current-steering DAC self-testing and calibration technique is proposed. In the proposed scheme, the lower bits of the DAC are duplicated and an analog comparator is added to facilitate self-testing and calibration. In selftesting mode, the controller executes the self-testing algorithm to characterize the DAC higher bits and computes the calibration information. In function mode, it produces the inputs to the duplicated lower bits for calibration. To validate the idea, a 14-bit prototype has been fabricated using TSMC 0.35 µm technology. The measurement results show that INL, DNL, and SFDR are significantly improved.