Patent ID: 9531181
Filing Date: 2016-12-27
CPC Classification: G01R,H02H,H03F

Claim Text:
1. A current sensing circuit, comprising: a first input terminal and a second input terminal for introducing a subject current from a device coupled between the first and second input terminals; a first amplifier having a first input node coupled to the first input terminal via a protection resistor, a second input node coupled to the second input terminal, and a first output node coupled to the first input node via a capacitor, wherein the first amplifier has a current sensing path for sensing the subject current and converting the subject current into an output voltage that changes with the subject current, and wherein the first amplifier further comprises a feedback path comprising an over-current protection device coupled between the first input terminal and the first output node of the first amplifier; and a protection circuit coupled between the first and second input nodes of the first amplifier, wherein the protection circuit is configured to draw a protection current from the first input terminal through the protection resistor to at least partially offset the subject current, and wherein the protection circuit is coupled in parallel with the feedback path, and the parallelly-coupled feedback path and protection circuit are further coupled in series with the current sensing path.