A Digital-to-Resistance Converter with an Automatic Offset Calibration Method for Evaluating Dynamic Performance of Resistive Sensor Readout Circuits

In this paper, a digital-to-resistance converter (DRC) with automatic offset calibration circuits is proposed. This circuit is used to evaluate the dynamic performance of resistive sensor readout circuits. The proposed DRC consists of a digital-to- analog converter, an analog multiplier, a fixed-value reference resistor, and current sources. A wide-range resistance changing at high frequency is achieved with the proposed DRC. In order to minimize the resistance error caused by the offset voltage of op- amps, an automatic offset calibration method is proposed. This developed prototype DRC achieved 96.3 dB dynamic range, 56.1 dB SNDR at 10kHz, and a maximum operating frequency is 100kHz.