SLLSFQ7 November 2023 MCF8329A
PRODUCTION DATA
Dead time is inserted between the switching instants of high-side and low-side MOSFET in a half bridge leg to avoid shoot-through condition. Due to dead time insertion, the expected voltage and applied voltage at the phase node differ based on the phase current direction. The phase node voltage distortion introduces undesired distortion in the phase current causing audible noise. The distortion in current waveform due to dead time appear as sixth harmonic of fundamental frequency in the dq reference frame. The MCF8329A integrates a proprietary dead time compensation, so that the current distortion due to dead time is alleviated. The dead time compensation can be enabled or disabled by configuring DEADTIME_COMP_EN. Even when DEADTIME_COMP_EN is set to 1b (compensation enabled), dead time compensation is disabled when motor electrical frequency exceeds 108-Hz.