8 Overcurrent Protection

Overcurrent protection is not covered in the code example, but it is still supported by the PWM module. The PWM PCI block also includes current limit shutdown capabilities with output pin overrides (CLDAT[1:0]). Unlike the user override, the shutdown of the PWM signals occurs immediately. The current-limit PCI can be configured for cycle-by-cycle overcurrent truncation or configured for latched shutdown with a manual termination/reset.

There are different approaches to bringing the current feedback to the microcontroller (output current, CT for primary tank current), but in all cases, utilizing the DAC+CMP module to interconnect to the current-limit PCI is essential. Each of the HB LLCs could select the same comparator output, or each of the banks could leverage their own OR’d feedback current through CTs, or each LLC could utilize its own CT plus comparator for cycle-by-cycle control. The implementation is specific to the application needs, but with the flexibility of the PWM and up to eight DAC+CMP modules, overcurrent protection can easily be supported in this dual multiphase converter.