Small Area, High Accuracy Sub-Radix Resistive Current Mode Digital-To-Analog Converter with Novel Calibration Algorithm

This paper presents a segmented 15-bit resistor-based current mode sub-radix digital-to-analog converter (DAC). The paper outlines equations that demonstrate the relationship between redundancy and the maximum positive jumps, providing insight into how area can be minimized during design. Furthermore, the paper introduces a new digital calibration algorithm, which represents an alternative to the typical successive approximation register (SAR) based approach used for sub-radix DAC structures. The proposed algorithm successfully calibrates the 15-bit output to obtain a linear 14-bit output with an INL of ±0.39 LSBs. The proposed circuit is modeled in MATLAB, and simulation results are presented, validating the equations presented and the performance of the circuit post-calibration.