Device in a power delivery circuit

A power delivery circuit for supplying load current to a load, comprising:

• a power FET device comprising a majority current device for supplying a majority current output to a load, a minority current device for supplying a minority current output, and a terminal whose voltage is representative of the voltage at the output of said majority current device;
• a current detection circuit for obtaining a signal proportional to said majority current output, the current detection circuit comprising:
• a voltage matching buffer circuit comprising first and second semiconductor devices, said first semiconductor device coupled to said minority current output and said second semiconductor device coupled to said terminal;
• and
• a current controlling circuit comprising third and fourth semiconductor devices driving said voltage matching buffer circuit so as to draw first and second currents through said first and second semiconductor devices, wherein said first and second currents are in a predetermined ratio;
• at least one output node for providing said signal proportional to said majority current output.

An improved current sensing circuit for use in combination with a current controlling device in a power delivery circuit for supplying load current to a load, the current controlling device being multi-cellular, and having parallel-connected major current-carrying cells for outputting a main device current and at least one minor current-carrying cell to output a current proportional to the main device current, the improvement in the current sensing circuit comprising:

• a buffer circuit comprising first and second semiconductor devices, said first semiconductor device coupled to the output of said minor current-carrying cell and said second semiconductor device coupled to output of said parallel-connected major current-carrying cells, for controlling voltage at the output of said at least one minor current-carrying cell;
• and
• a current controlling circuit comprising third and fourth semiconductor devices driving said buffer circuit so as to draw first and second currents through said first and second semiconductor devices, wherein said first and second currents are in a predetermined ratio;
• at least one output node for providing a signal proportional to said main device current.

An improved current sensing circuit for use in combination with a current controlling device in a power delivery circuit for supplying load current to a load, the current controlling device being multi-cellular, and having parallel-connected major current-carrying cells for outputting a main device current and at least one minor current-carrying cell to output a current proportional to the main device current, the improvement in the current sensing circuit comprising:

• a buffer circuit comprising first and second semiconductor devices, said first semiconductor device coupled to the output of said minor current-carrying cell and said second semiconductor device coupled to output of said parallel-connected major current-carrying cells, for controlling voltage at the output of said at least one minor current-carrying cell;
• and
• a current controlling circuit comprising third and fourth semiconductor devices driving said buffer circuit so as to draw first and second currents through said first and second semiconductor devices, wherein said first and second currents are in a predetermined ratio;
• fifth and sixth semiconductor devices interposed in series connection between said buffer circuit and said current controlling circuit;
• and,
• at least one output node for providing a signal proportional to said main device current.