An Ultra-Low Quiescent Current Under-Voltage Lockout Circuit for a High-Voltage Gate Driver IC

Abstract

An ultra-low quiescent current under-voltage lockout (UVLO) circuit for a high-voltage gate driver integrated circuit (HVIC) is described for application in portable devices. The UVLO circuit consumes the static current in the high-side circuitry and the resistive divider used to detect the supply-voltage was the major consumer of power in the circuit. Hence, a supply-voltage sensor based on a diode-connected metal–oxide–semiconductor field-effect transistor (MOSFET) with a voltage limiter design is proposed to ensure low power consumption. Unlike the conventional UVLO design, where a resistive divider is used, the proposed structure dissipates the negligible current at a low supply-voltage and significantly reduces the static current at the nominal and high supply-voltage. The high-side quiescent current using the proposed design and the conventional designs at various supply-voltage levels are analyzed. In the proposed structure, the size of the voltage sensor is considerably smaller when compared with those in conventional designs.