2 results about "Miller effect" patented technology

This invention relates to the field of drive circuit technology, and discloses a highly reliable gate drive circuit, drive chip, and power semiconductor device. The circuit breaks through the existing passive compromise scheme that relies solely on adjusting the turn-off resistor. It uses a detection unit to collect the gate voltage of the IGBT unit in real time, a latch unit to output a stable square wave signal when the voltage reaches a preset threshold, and a pull-down unit to simultaneously provide a low-impedance discharge path, actively suppressing abnormal gate voltage rise caused by the Miller effect. The design of the Miller suppression unit avoids the switching speed reduction and device overheating problems caused by increasing the turn-off resistor, while effectively suppressing the risk of mis-turn-on caused by crosstalk between the upper and lower bridge arms, achieving dual optimization of crosstalk suppression and switching performance. This significantly improves the reliability and stability of the gate drive, extends the lifespan of the power semiconductor device, and is suitable for various power topologies such as half-bridge and full-bridge, with wide application scenarios and strong practicality.

The application discloses a Miller effect elimination circuit, which is electrically connected between a control electrode of a power semiconductor device and a first current-carrying terminal, and comprises an elimination trigger circuit and an energy storage capacitor. The elimination trigger circuit is activated during the turn-off of the power semiconductor device in response to a control signal, and connects the energy storage capacitor in parallel between the control electrode and the first current-carrying terminal while applying a turn-off negative voltage to the control electrode. At this time, the energy storage capacitor, together with a Miller capacitor, a parasitic capacitor and a loop parasitic inductance of the power semiconductor device, forms a low-frequency resonance network. The application solves the problems of the suspended gate and high-frequency resonance in the traditional scheme, and is suitable for reliable driving of SiC MOSFET, IGBT and other devices in high-voltage high-speed switching occasions.