Patent ID: 7519335
Filing Date: 2009-04-14
Classification: H03D

Abstract:
1. A mixer device for a transmission system comprising: a signal input terminal for receiving an input voltage that is representative of a modulating signal; two differential input terminals receiving two high-frequency signals in phase opposition relative to one another; a pair of first and second output terminals for delivering two currents that are representative of the high-frequency signals modulated by the modulating signal; a pair of transistors forming a differential circuit having two differential control inputs each coupled to one of the differential input terminals, two differential current outputs respectively coupled to the pair of output terminals and a common current output whose current is equal to a sum of the differential output currents; a current-to-voltage conversion element coupled to the common current output of the pair of transistors, capable of transforming the current delivered by this output into an output voltage; an amplifier having a positive input, a negative-feedback input and an output, wherein the amplifier is capable of delivering at its output an amplified signal that is representative of a signal present at the positive input, the positive input being coupled to the signal input terminal, the negative-feedback input being coupled to the current-to-voltage conversion element, and the output being coupled to each of the differential control inputs of the pair of transistors.