Patent ID: 6400187
Filing Date: 2002-06-04
Classification: H03F

Abstract:
A transimpedance circuit comprising:an amplifier having first and second inputs and an output; first and second current sense resistors; a first differential coupling circuit coupled between said first current sense resistor and said first and second inputs of said amplifier, and being operative to apply a first differential input current to said first and second inputs of said amplifier in accordance with a first voltage across said first current sense resistor; a second differential coupling circuit coupled between said second current sense resistor and said first and second inputs of said amplifier, and being operative to apply a second differential input current to said first and second inputs of said amplifier in accordance with a second voltage across said second current sense resistor; and a compensator circuit coupled between a supply voltage node and said first and second inputs of said amplifier, and being operative to close a negative feedback path from said output to said first input of said amplifier, relative to a voltage balancing path coupled to said second input of said amplifier, and equalize voltages applied thereby to said first and second inputs of said amplifier, irrespective of variations in currents through said first and second current sense resistors.