CMOS upconversion mixer with filterless carrier feedthrough cancelation and output power tuning

The synthesis, design and implementation of a CMOS upconversion mixer that both can adjust, by means of a DC voltage control, its output power and that cancels the carrier feedthrough is presented. Aiming at very low cost medical implant applications, a prototype of the architecture was implemented in a double poly, three metal layers, 0.5 μm CMOS technology. For a range between one half and one fifth of the supply voltage, the circuit can decrease in a quadratic form the power delivered to the load until one forth of its maximum value by varying the DC component at the baseband signal. In addition, a large IIP3 is attained since the closest high order intermodulation product present in the spectrum of the signal is far from the vicinity of the component of interest.