Low Power and Wide Gain-Range Mixer Using Current-Bleeding Variable-Gain Amplification

Abstract

This paper presents a mixer with low power and a wide gain-range using a current-bleeding variable-gain amplifier (VGA) technique. The proposed 2.4-GHz mixer controls the conversion gain by replacing a conventional current-bleeding stage with the VGA while maintaining the low-power function of current-bleeding. The VGA is composed of a common-source (CS) amplifier, a current controller, and a variable load. It has a wide variable-gain range by changing transconductance (gm) of the CS amplifier and output resistance of the variable load stage. The proposed mixer is fabricated in 65-nm CMOS process. The measured results showed a conversion gain of 20.5 dB, a variable-gain range of more than 45 dB, a third-order input-intercept point (IIP3) of -14.4 dBm, and power consumption of 5.4 mW at a 1.2-V supply voltage.