| 摘要 |
A current-sense circuit for measuring a load current in a switching power regulator may operate independently of process variation and temperature, and measure bi-directional load currents without requiring high-speed, high-voltage amplifiers for operation. A positive sense voltage may be generated for positive and/or negative values of a switch current conducted by a power switching device in the switching power regulator, by applying a linear transformation to a switch voltage developed across the power switching device according to the switch current. A first sense current may be generated by applying the positive sense voltage across a matching switching device having a same channel length as the power switching device. A second sense current may be generated independently of the switch voltage, and a total sense current that is proportional to the switch current may be calculated by subtracting the second current from the first current. The ratio of the total sense current and the switch current will be independent of process variation and temperature.
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