A differential implementation of the CMOS active-load body-effect mixer

This paper describes the implementation of a new mixer topology. The two input signals applied respectively to the back gate and the gate of two transistors achieve the mixing thanks to the active load body effect. The theoretical study of this effect is presented. Owing to the differential structure, the final circuit provides a conversion gain of more than 10 dB and reaches a 14 dB NF. The linearity is better than -5 dBm IIP3 while the architecture draws only 12 mW. Implemented in a 0.18 μm CMOS VLSI technology, the circuit, dedicated to 3G mobile phone operates at 1.8V voltage supply.