SLLSFQ7 November 2023 MCF8329A
PRODUCTION DATA
Coast (Hi-Z) mode is configured by setting MTR_STOP to 000b. When motor stop command is received, the MCF8329A turns off all the external MOSFETs creating Hi-Z state at the phase motor terminals. When the MCF8329A transitions from driving the motor into a Hi-Z state, the inductive current in the motor windings continues to flow and the energy returns to the power supply through the body diodes in the MOSFET output stage (see example Figure 7-40).
In this example, current is applied to the motor through the high-side phase-A MOSFET (HSA), high-side phase-B MOSFET(HSB) and returned through the low-side phase-C MOSFET (LSC). When motor stop command is received all 6 MOSFETs transition to Hi-Z state and the inductive energy returns to supply through body diodes of MOSFETs LSA, LSB and HSC.