Power regulator with prevention of inductor current reversal

A switching regulator system, comprising:

• a first power transistor coupled between an input voltage node and a first switch node;
• a second power transistor coupled between the first switch node and a ground;
• an inductor coupled between the first switch node and an output voltage node;
• a first capacitor coupled between the output voltage node and ground;
• and
• a third replica transistor coupled between the input voltage node and a second switch node, the third replica transistor being a replica of the first power transistor;
• a fourth replica transistor coupled between the second switch node and ground, the fourth replica transistor being a replica of the first power transistor;
• a resistor coupled to the second switch node;
• a transconductance stage including a first input coupled to the resistor and a second input coupled to the output voltage node;
• and
• a fifth switch coupled between the first and second inputs of the transconductance stage.

A voltage synthesizer for at least partially regulating a switching regulator that includes first and second power transistors, the voltage synthesizer comprising:

• a synthesizer input coupled to an input of the switching regulator;
• a first replica transistor coupled between the synthesizer input and a first node, the first replica transistor being a replica of the first power transistor;
• a second replica transistor coupled between the first node and ground, the second replica transistor being a replica of the second power transistor;
• a resistor coupled between the first node and a second node;
• a capacitor coupled between the second node and ground;
• a transconductance stage to compare a voltage of the capacitor received on a first input of the transconductance stage to the output voltage of the switching regulator received on a second input of the transconductance stage and to generate an output signal in response to the comparison;
• and
• a third switch coupled between the first and second inputs of the transconductance stage;
• wherein the third switch is turned on during each cycle of operation of the voltage synthesizer to reset the capacitor voltage to the output voltage of the regulator.