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

Abstract

In this paper, a low phase noise and low power 5.15 GHz LC-tank VCO is presented and analysed. The phase noise achieved is −91, −116 and −126 dBc/Hz at 100 KHz, 1 MHz and 3 MHz offsets respectively from the carrier frequency of 5.15 GHz, with 1.8 V power supply voltage and giving a very low power consumption of about 2.5 mW by considering the proposed oscillator topology, which consumes less power than the classical oscillator using the traditional differential transconductor pair. A broad tuning range has been achieved by means of standard mode PMOS varactors. The tunability of the designed VCO covers 530 MHz, from 4.78 GHz up to 5.31 GHz. Predicted performance has been verified by analyses and simulations using ELDO-RF tool with 0.35 µm CMOS TSMC parameters.