STx5NK52ZD Power MOSFETs
New family of SuperFREDmesh^TM devices for brushless DC motors

In order to provide a six-step current to a motor, the power stage utilizes six Power MOSFETs that can switch in different specific sequences. One popular switching mode is shown in the diagram below. It provides a sixstep current, and is made up of three Power MOSFETs: Q1, Q3 and Q5 switching at high frequency, and Q2, Q4 and Q6 switching at low frequency. The powering stage occurs when a low frequency Power MOSFET is in ON-state and a high frequency one is switching. During turn-on high frequency Power MOSFETs suffer the recovery current contribution of the intrinsic diode in the low frequency devices. In order to reduce the losses during turn-on, the performance of the body diode must be improved. Therefore, a Power MOSFET with a fast recovery diode has been developed. When the diode is reverse biased after its conduction, the reverse current spike Irrm is smaller and the time needed to complete the recovery is shorter than if a standard Power MOSFET were used.

Typical 3-phase inverter topology for BLDC motor drive
using six Power MOSFETs