Patent ID: 7825735
Filing Date: 2010-11-02
Classification: H03F

Abstract:
1. A transimpedance amplifier system to receive an input current signal and to generate therefrom a low-gain output signal and a high-gain output signal, comprising: a transimpedance amplifier having a first resistor connected between an output of the transimpedance amplifier and an input thereof, and with a series-connected combination of a diode and a second resistor being connected between the output of the transimpedance amplifier and the input thereof, with an anode side of the diode being connected to the output of the transimpedance amplifier, and with a cathode side of the diode being connected to the second resistor at a node therebetween; and a signal linearizer having a first linearizer input connected to the amplifier output to receive a first voltage signal generated from the input current signal by the transimpedance amplifier, and a second linearizer input connected to the node between the diode and the second resistor to receive a second voltage signal generated from the input current signal by the transimpedance amplifier, and with the signal linearizer scaling down the first voltage signal to form a scaled-down first voltage signal and scaling up the second voltage signal to form therefrom a scaled-up second voltage signal, and with the signal linearizer adding the scaled-down first voltage signal to the second voltage signal to generate the low-gain output signal, and with the signal linearizer adding the scaled-up second voltage signal to the first voltage signal to generate the high-gain output signal, and with the low-gain output signal and the high-gain output signal both being linearly related to the input current signal.