START-UP TECHNIQUE AND SYSTEM FOR A SELF-POWERED GATE DRIVE CIRCUIT

摘要

A power transistor system (200) comprises; - a first power transistor (12a, 16a); - a first gate drive circuit (10a) comprising a first (C) and second (Cp) supply capacitor, the first gate drive circuit electrically coupled to the first power transistor; - a first switch (sw1), the first switch electrically coupling a single-supply voltage node (Vp) with the first supply capacitor (C) of the first gate drive circuit when closed; and - a control module configured to: signal the first switch (sw1) to close; signal the first gate drive circuit to switch on the first power transistor, the first gate drive circuit configured to apply a current supplied by a discharge of the first supply capacitor (C) of the first gate drive circuit to the gate (G) of the first power transistor; and signal the first gate drive circuit to switch off, wherein the first gate drive circuit is configured to re-charge the first supply capacitor of the first gate drive circuit by applying a current supplied by a discharge of the respective second supply capacitor (Cp) to the first capacitor (C).