A 0.35-V 520- $\mu \text{W}$ 2.4-GHz Current-Bleeding Mixer With Inductive-Gate and Forward-Body Bias, Achieving >13-dB Conversion Gain and >55-dB Port-to-Port Isolation

Abstract

An ultralow voltage micropower 2.4-GHz current-bleeding active mixer for energy-harvesting Bluetooth low energy/ZigBee applications is reported. It features a double-balanced mixer topology combining nMOS current-bleeding transistors with a pMOS local oscillator switching quad, and forward-body bias and inductive-gate bias techniques to secure an adequate performance at a supply voltage down to 0.35 V. Fabricated in 0.13- $\mu \text{m}$ CMOS, the prototype exhibits a conversion gain of 13.77 dB, a third-order intercept point of −3.5 dBm, and a noise figure of 18 dB. The power consumption is $520~\mu \text{W}$ , and port-to-port isolation is >55 dB. The achieved figure of merit compares favorably with the state of the art.