Design Of 2.4 GHz CMOS Low Power VCO

VCO(Voltage controlled oscillator,VCO)as the key components in wireless communication system,it is widely used in the RF communication circuits such as phase-locked loop system mainly as the role of the local oscillator signal generator,provide stable carrier signal transceiver.2.4 GHz frequency band and it is widely used in the field of wireless communication and low power consumption also today's wireless communication system development goals.So this article is based on TSMC 0.18 ?m CMOS process design of low-power 2.4 GHz CMOS voltage-controlled oscillator has great practical value.At the same time in the design process in order to meet the requirements of low tuning gain and wide tuning range,this paper adopted four binary switch capacitor array,while broadening the operating frequency range has reached the design goal of reducing tuning gain.To reduce the power consumption of the circuit,and the core circuit adopts the complementary cross coupling structure.To reduce the phase noise at the same time,considering the feasibility in the practical application circuit,in the tail current source using second harmonic filtering technology.Based on the variable capacitance access circuit is optimized,the variable capacitance voltage on both ends,the regulation of enhancing the tuning voltage utilization.The simulation results show that after the work frequency of the VCO is 2.3 to 2.8 GHz,maximum tuning gain below 110 MHz/V,phase noise below-100 dBc/Hz@1MHz,power consumption is less than 1.8mW,various performance indicators meet the design requirements.In this paper,design the voltage-controlled oscillator can be used in the 2.4 GHz wireless sensor network phase-locked loop circuits.