A 5-GHz low-voltage and low-power CMOS LC VCO for 802.11a wireless LAN applications

In this paper, a fully integrated 5.3 GHz low phase noise LC-tank voltage controlled oscillator is presented and analyzed. The phase noise achieved is -91, -116 and -126 dBc/Hz at 100KHz, 1MHz and 3MHz offsets respectively from the carrier frequency of 5.3 GHz, with 1.8 V power supply voltage and giving a low power consumption of about 3.5 mW by adopting the proposed oscillator topology, which exhibits less power consumption than the traditional VCO using the classical differential transconductor pair. A broad tuning range has been achieved by using the standard mode PMOS varactors in the proposed oscillator architecture. The tunability of the designed VCO covers 530 MHz, from 4.78 GHz up to 5.31 GHz.