A CMOS reconfigurable passive mixer with digitally-controllable gain

This paper presents a reconfigurable current-commutating passive mixer for multi-standard applications. By having controllable transconductance and transimpedance stages, the gain, noise figure and linearity of the mixer can be reconfigured. Fabricated in 0.18 μm CMOS process, the mixer achieves a voltage-conversion-gain from 4 to 22 dB. The measured maximum IIP3 is 8.5 dBm and the minimum noise figure is 8.0 dB. The current consumption for a single branch (I or Q) ranges from 3.1 to 5.6 mA from a 1.8 V supply voltage. The chip occupies an area of 0.705 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> including pads.