US Patent 10355590 Boost converter with pre-charge current

Method and apparatus is disclosed for providing a controlled pre-charging current for capacitive loads coupled to a boost converter. For at least some embodiments, the boost converter may include a high-side field effect transistor (FET) and a low-side FET. The boost converter may provide the pre-charge current by periodically enabling the high-side FET while the low-side FET is maintained in an off state. The high-side FET may be enabled by a square-wave signal. The pre-charge current may be delivered until the output voltage of the boost converter exceeds a reference voltage. After the output voltage exceeds the reference voltage, the boost converter may transition to a normal (switching) operation.