SLLSFQ7 November 2023 MCF8329A
PRODUCTION DATA
The MCF8329A uses 12-bit timers to estimate the time during the current ramp up in IPD, when the motor start-up is configured as IPD (MTR_STARTUP is set to 10b). During IPD, the algorithm checks for a successful current ramp-up to IPD_CURR_THR, starting with an IPD clock of 10MHz; if unsuccessful (timer overflow before current reaches IPD_CURR_THR), IPD is repeated with lower frequency clocks of 1MHz, 100kHz, and 10kHz sequentially. If the IPD timer overflows (current does not reach IPD_CURR_THR) with all the four clock frequencies, then the IPD_T1_FAULT gets triggered. The user can enable IPD timeout (IPD timer overflow) by setting IPD_TIMEOUT_FAULT_EN to 1b.
IPD gives incorrect results if the next IPD pulse is commanded before the complete decay of current due to present IPD pulse. The MCF8329A can generate a fault called IPD_FREQ_FAULT during such a scenario by setting IPD_FREQ_FAULT_EN to 1b. The IPD_FREQ_FAULT maybe triggered if the IPD frequency is too high for the IPD current limit or if the motor inductance is too high for the IPD frequency and IPD current limit.