Abstract: The invention relates to the field of power semiconductor devices. This invention discloses a drive circuit and device of a power switch. The input terminal of the drive circuit receives a pulse signal; the output terminal of the drive circuit is connected to a capacitor circuit. The capacitor circuit is used to provide a negative voltage for a first electrode of the power switch to turn off the power switch when the pulse signal is a turn-off signal; the drive circuit includes a capacitance adjustment unit. The capacitance adjustment unit includes a negative voltage adjustment element that can charge a capacitor whose voltage is lower than a predetermined voltage when the pulse signal is the turn-off signal.