Patent ID: 7570115
Filing Date: 2009-08-04
Classification: H03F

Abstract:
1. A device for extracting a common mode voltage of an input signal, comprising: an operational amplifier having an output, at least one negative input and at least one positive input; a first transistor, a first terminal of the first transistor being operably coupled to the output of the operational amplifier; a second transistor, a terminal of the second transistor being operably coupled to a second terminal of the first transistor and the at least one positive input of the operational amplifier to create a negative feedback loop; third and fourth transistors, a first terminal of the third transistor and a first terminal of the fourth transistor both being operably coupled to the at least one negative input; and a common mode output, wherein the negative feedback loop extracts the common mode voltage of the input signal, the common mode voltage of the input signal being output at the common mode output.