Multi-level charge pump circuit

A multi-level charge pump (MCP) circuit, comprising:

• an MCP comprising a multi-level voltage circuit, the multi-level voltage circuit comprises:
• an input node that receives a supply voltage;
• an output node that outputs a low-frequency voltage;
• a first switch path having a first on-resistance and is coupled between the input node and the output node;
• and
• a second switch path having a second on-resistance and coupled between the input node and the output node in parallel to the first switch path, the second switch path comprising a first fly capacitor to be charged to provide a first boost voltage between the input node and the output node to thereby boost the low-frequency voltage above the supply voltage;
• and
• a third switch path having a third on-resistance and coupled between the input node and the output node in parallel to the first switch path and the second switch path, the third switch path comprising a second fly capacitor to be charged to provide a second boost voltage between the input node and the output node to thereby boost the low-frequency voltage above the supply voltage;
• and
• a control circuit configured to:
• in a buck mode operation, activate the first switch path and at least one of the second switch path and the third switch path to cause the multi-level voltage circuit to output the low-frequency voltage at the supply voltage with an equivalent resistance smaller than the first on-resistance;
• and
• in a boost mode operation, deactivate the first switch path and activate one of the second switch path and the third switch path in response to a respective one of the first boost voltage and the second boost voltage being above a voltage threshold to cause the multi-level voltage circuit to maintain the low-frequency voltage above the supply voltage.