Low-Voltage Bulk-Driven Mixers in 45nm CMOS for Ultra-Wideband TX and RX

Abstract

This paper presents fully differential up-and down-conversion mixers manufactured in a triple well 45 nm standard CMOS process for low voltage UWB TX and RX applications. The proposed circuits both employ the transistor bulk terminal for signal injection. While the RX mixer uses the bulk for switching via threshold voltage modulation, the TX mixer applies the baseband signal to the bulk. Both circuits offer resistive on-chip termination and DC coupled output buffering for measurement purposes. The RX mixer features a maximum conversion gain of 9.4 dB at 2.5 GHz and an input-referred compression point of -13 dBm while the 3-dB low-pass bandwidth is beyond 10 GHz. The TX mixer offers a maximum conversion gain of -8.8 dB at 5.5 GHz and an output-referred compression point of -10.3 dBm. The operational bandwidth ranges from 4.5 GHz to 7 GHz. Both circuits operate at a low voltage power supply of 1.1 V.