Electromagnetic interference of power MOSFET with bridge drive and its suppression

In order to eliminate the oscillation of the MOSFET gate, a circuit model of the half-bridge inverter considering stray parameters of the drive circuit is put forward based on the MOSFET model. By analyzing the circuit topology the oscillation is caused by the high dv/dt produced during the power MOSFET switching and junction capacitance and distributed inductance. The drive circuit parameters are devised according to the transient timing domain three-dimensional relationship curves of parameters responding to the oscillation. The oscillation can be obviously suppressed with enhancing MOSFET turn-on time. Both the theoretical analysis and experimental results indicate that the improved circuit can meet the MOSFET drive requirement.