CONTROLLING A HIGH-SIDE SWITCHING ELEMENT USING A BOOTSTRAP CAPACITOR

A monolithic integrated circuit for controlling a high-side switching element for a load using a bootstrap capacitor is disclosed. The integrated circuit comprises a first supply voltage input for receiving a first input supply voltage V1, a second supply voltage input for receiving a second, current-limited input supply voltage VCP, a voltage-sensing input for receiving a source voltage, a first output for providing a drive signal VG to the switching element, a second output for providing a charging signal VBS to a bootstrap capacitor, a pre-driver for generating the drive signal, the pre-driver having a voltage input and an output which is coupled to the first output, and a power supply control section comprising first and second switches. The first and second switches are arranged in series between the first input and the second output, the second input is coupled to a node between the first and second switches, and the second node is coupled to a voltage input of the pre-driver. The first and second switches are selectively operable following switching of the switching element from an ON state to an OFF state and in response to a determination that the source voltage is below a predetermined level, to decouple the second output and in response to determination that the source voltage is above the predetermined level to couple the second output to the second output.