Current sense amplifier and method

摘要

A current sense amplifier (10) for measuring current flowing through a sense resistor (12) coupled between first (11) and second (13) terminals, respectively, of the current sense amplifier, the current sense amplifier includes a first amplifier (18) having a first input (17) coupled by a first resistor (16) to the first terminal (11) and a second input (20) coupled by a second resistor (19) to the second terminal (13) and a bias circuit (30,24) coupled to the first input (17) of the first amplifier for causing the bias current to flow through the first resistor (16. A feedback transistor (26) is coupled to the output (22) of the first amplifier and the second input (20) of the first amplifier to cause a feedback current to equalize the voltages on the first (17) and second (20) inputs of the first amplifier and supply the feedback current to an output terminal (36) of the current sense amplifier (10).