SLLSFQ7 November 2023 MCF8329A
PRODUCTION DATA
MCF8329A provides a way to precharge the bootstrap capacitor during start-up. The algorithm uses a sequence to charge each phase bootstrap capacitor by turning on the external low-side MOSFETs using PWM turn-on pulses on GLx pins as shown in Figure 7-17. In the charging sequence, the low side MOSFET is switched at a frequency set by PWM_FREQ_OUT with an on time of tLS_ON_BC (5% on time duty cycle). Each phase is charged for a period equal to one third of BST_CHRG_TIME.