Fully-integrated multi-standard VCOs with switched LC tank and power controlled by body voltage in 130nm CMOS/SOI

In this paper, the design of two VCOs for wireless multi-standard applications is presented. These circuits have been produced using CMOS/SOI technology, with body voltage to control power consumption and phase noise performance. A new architecture for multi-standard applications is proposed. To our knowledge, this is the first structure using a balun to change the oscillation frequency and the body biasing to control VCO core current. Four standards are covered by these structures: GSM (900MHz), DCS (1.8GHz), Bluetooth (2 GHz) and 802.11a (0.8GHz). The tuning range can vary from 80 MHz to 0.8GHz by using frequency divider, adjusted varactor and switched LC tank. The main idea is to use only two MOS varactors to cover the entire frequency span. The first one is needed to get the matched frequency variation and the second to adjust the oscillation frequency. Such VCOs can be made thanks to CMOS/SOI technology advantages, high-Q passives and body voltage biasing that allow current control and switched LC tank. At a frequency offset of 100kHz, the single side band phase noise measurements were -82dBc/Hz and -102dBc/Hz at 0.2GHz and 1.8GHz respectively