Regulated supply for power conversion system control circuitry

A power circuit to provide power to control circuitry of a multilevel power conversion system with a flying capacitor, the power circuit comprising:

• a regulator, including:
• a regulator input to receive a regulator input voltage signal;
• and a regulator output coupled to provide a supply voltage signal to the control circuitry, and
• a power switching circuit, coupled with the capacitor, to couple the regulator input to a first terminal of the flying capacitor in response to a second terminal of the flying capacitor being coupled to a reference voltage node in a given switching cycle of the power conversion system, and to couple the regulator input to the second terminal of the flying capacitor in response to the first terminal of the flying capacitor being coupled to an input node of the power conversion system in the given switching cycle.

A method of controlling a multi-level power conversion system with a flying capacitor, the method comprising:

• generating pulse width modulated signals having a duty cycle to operate switches to convert an input signal at an input node into an output signal at an output node, the duty cycle being adjustable in different switching cycles;
• generating a regulator input voltage signal from a selected terminal of the flying capacitor;
• and
• regulating the regulator input voltage signal to provide a supply voltage signal to control circuitry of the power conversion system.