DC-DC converter switching transistor current measurement technique

摘要

A method is described comprising conducting a first current through a switching transistor. The method also comprises conducting a second current through a pair of transistors whose conductive channels are coupled in series with respect to each other and are together coupled in parallel across the switching transistor's conductive channel. The second current is less than and proportional to the first current.

主权项

1. An apparatus, comprising:
a direct-current to direct-current (DC-to-DC) converter circuit including
a current measurement circuit having a first pair of transistors with respective channels of the first pair of transistors coupled in series, a drain of a first transistor of the first pair of transistors coupled to a first end of a conductive channel of a switching transistor, and a source of a second transistor of the first pair of transistors coupled to a second end of the channel of the switching transistor;an amplifier having a measurement leg coupled to a node between the first pair of transistors; anda second pair of transistors with respective channels of the second pair of transistor being coupled in parallel, a node between the second pair of transistors being coupled to a reference leg of the amplifier.