Circuit Techniques for Enhancing Output Current Accuracy in Floating Gate Drivers

This paper introduces two innovative circuit techniques developed to dynamically compensate output current variations in high-voltage floating gate drivers. They can be efficiently used during both charge and discharge phases, significantly reducing the sensitivity of the output current to supply voltage fluctuations. A summary of prior art is presented, reviewing a conventional gate driver architecture and its associated challenges, particularly the limitations arising from supply voltage variations that cause output current inaccuracies. These shortcomings are highlighted as key motivations for the proposed advancements. In addition to introducing the compensated architectures, the paper provides a comparative analysis of the conventional and improved designs. This analysis highlights enhancements in driving accuracy while maintaining area efficiency. One of the proposed techniques has been successfully implemented in the design of a gate driver for motor control using a standard high-voltage 0.18μm BCD technology. The proposed solutions improve performance significantly, reducing output current deviation from 25% in uncompensated designs to below 2% across the full output range (1mA – 150mA). Experimental results confirm the accuracy of the simulations, validating the effectiveness of the proposed approach.