A switched-current incremental A/D converter

This paper presents the implementation of an incremental A/D converter designed as part of the signal-conditioning circuitry of a pressure sensor interface. For technological compatibility, the switched-current technique was chosen, since it does not need double polysilicon CMOS process. The low precision of the SI technique have been partially overcome by using a offset cancellation algorithm and circuit enhancements. Resolutions of up to 10 bits are achieved for a 1 MHz clock frequency through electrical simulations. A 1 μm CMOS prototype is being tested and some experimental results are given