Patent ID: 6573789
Filing Date: 2003-06-03
Classification: H03F

Abstract:
A signal processing circuit, comprising:an inner stage circuit comprising: a first low gain amplifier having an input and an output; and a first positive feedback circuit coupling the output of the first low gain amplifier to the input of the first low gain amplifier; the positive feedback circuit including a floating signal source, a first feedback element coupled in series with the floating signal source at a first output current node, and an inner second stage circuit coupled to the first output current node; the floating signal source producing a first voltage that is impressed across the first feedback element and processed by the first feedback element into a first output current signal; and an outer stage circuit coupled to the inner second stage circuit of the inner stage circuit for receiving the first output current signal therefrom, the outer stage circuit comprising: a second low gain amplifier having an input and an output; and a second positive feedback circuit coupling the output of the second low gain amplifier to the input of the second low gain amplifier; the second positive feedback circuit including the inner stage circuit, a second feedback element coupled in series with the inner stage circuit at a second output current node, and an outer second stage circuit coupled to the second output current node; the inner stage circuit producing a second voltage that is impressed across the second feedback element and processed by the second feedback element into a second output current signal.