Variable switching frequency switched tank converters and associated methods

A variable switching frequency switched tank converter (STC), comprising:

• a first resonant tank circuit;
• a first pair of switching devices configured to drive the first resonant tank circuit;
• a first control signal configured to control the first pair of switching devices;
• a second pair of switching devices configured to drive the first resonant tank circuit;
• a second control signal configured to control the second pair of switching devices;
• and
• a controller configured to:
• control the first pair of switching devices and the second pair of switching devices to drive the first resonant tank circuit at a first frequency and with a first fixed on-time and a first phase difference between the first and second control signals, to obtain a first fixed ratio of output voltage of the STC to input voltage of the STC, while the STC is powering a load having a first magnitude, and
• control the first pair of switching devices and the second pair of switching devices to drive the first resonant tank circuit at a second frequency and with the first fixed on-time, and a second phase difference between the first and second control signals to obtain the first fixed ratio of output voltage of the STC to input voltage of the STC, while the STC is powering a load having a second magnitude, the second frequency being smaller than the first frequency and the second magnitude being smaller than the first magnitude.