JAJSPC5 December 2022 DRV8316C
PRODUCTION DATA
Active demagnetization reduces power losses in the device by turning on the MOSFETs automatically when the body diode starts conducting to reduce diode conduction losses. It is used in trapezoidal commutation when switching commutation states (turning a high-side MOSFET off and another high-side MOSFET on while keeping a low-side MOSFET on). Active demagnetization is enabled when EN_ASR and EN_AAR bits are set in the SPI variant or OCP/SR pin is set to Mode 3 or Mode 4 in the H/W variant.
When switching commutation states with active demagnetization disabled, dead time is inserted and the low-side MOSFET’s body diode conducts while turning another high-side MOSFET on to continue sourcing current through the motor. This conduction period causes higher power losses due to the forward-bias voltage of the diode and slower dissipation of current. Figure 9-2 shows the body diode conducting when switching commutation states.