A highly accurate solenoid valve driver with current sensing circuits for brake systems

Abstract

In this paper, we propose a highly accurate solenoid valve driver with high-and low-side current sensing circuits. The proposed solenoid valve driver improves the current accuracy by sensing the current of the solenoid coil alternately in the on-and off-states of the power MOS transistor. In the on-state, the low-side sensing circuit senses the current flowing through the low-side transistor. In the off-state, the high-side sensing circuit senses the current flowing through the high-side transistor. The proposed solenoid valve driver was implemented using a 0.11 mu m BCDMOS process. The measurement results show that the proposed solenoid valve driver achieves a high current accuracy of less than +/- 4% over the entire current range from 0 A to 2.25 A.