Current sensing in an on-die direct current-direct current (DC-DC) converter for measuring delivered power

A method of sensing a current in a direct current-direct current (DC-DC) converter, comprising:

• generating a mirror current based on a driver current in a high side driver (HSD) circuit, in response to a HSD control signal;
• amplifying a difference between a driver voltage at an output node of the HSD circuit and a mirror voltage at an output node of a current mirror circuit;
• generating a voltage equalizing signal on an output port of an amplifier circuit representing the amplified difference between the mirror voltage and the driver voltage;
• and
• adjusting the mirror voltage at the output node of the current mirror circuit corresponding to the driver voltage, in response to the voltage equalizing signal.

A power distribution circuit, comprising:

• a direct current-direct current (DC-DC) converter comprising a high side driver (HSD) circuit coupled to a supply voltage rail and an inductor;
• and
• a current sensing circuit, comprising:
• a power supply node coupled to the supply voltage rail;
• a control node coupled to the HSD circuit of the DC-DC converter to receive a HSD control signal;
• an amplifier circuit, comprising:
• a first input port coupled to a current mirror circuit;
• and
• a second input port configured to be coupled to an output node of the HSD circuit;
• and
• a cascode circuit coupled to the current mirror circuit and the amplifier circuit, the cascode circuit comprising:
• an output port coupled to a sensing node;
• and
• a cascode control port coupled to the amplifier circuit.

A current sensing circuit, comprising:

• a plurality of buck converter circuits of a direct current-direct current (DC-DC) converter, wherein each buck converter circuit among the plurality of buck converter circuits comprises a high side driver (HSD) circuit, a current mirror circuit, and a control node configured to receive a HSD control signal, each HSD circuit comprising a driver output node, and each current mirror circuit comprising a mirror output node;
• an amplifier circuit comprising a first input port coupled to the mirror output node of each current mirror circuit of the plurality of buck converter circuits, a second input port coupled to the driver output node of each HSD circuit of the plurality of buck converter circuits, and an amplifier output port;
• and
• a cascode circuit configured to couple the plurality of buck converter circuits to a sensing node based on a voltage equalizing signal generated on the amplifier output port.