A 0.7 V 6.66–9.36 GHz wide tuning range CMOS LC VCO with small chip size

ABSTRACT

The circuit designs are based on TSMC 0.18 μm CMOS standard technology model. The designed circuit uses transformer coupling technology in order to decrease chip area and increase the Q value. The switched-capacitor topology array enables the voltage-controlled oscillator (VCO) to be tuned between 6.66 and 9.36 GHz with 4.9 mW power consumption at supply voltage of 0.7 V, and the tuning range of the circuit can reach 33.7%. The measured phase noise is −110.5 dBc/Hz at 1 MHz offset from the carrier frequency of 7.113 GHz. The output power level is about −1.22 dBm. The figure-of-merit and figure-of-merit-with-tuning range of the VCO are about −180.7 and −191.25 dBc/Hz, respectively. The chip area is 0.429 mm² excluding the pads. The presented ultra-wideband VCO leads to a better performance in terms of power consumption, tuning range, chip size and output power level for low supply voltage.

KEYWORDS:

• Word
• ultra-wideband
• low-voltage
• voltage-controlled oscillator (VCO)
• phase noise

Acknowledgements

The authors would like to thank National Science council (NSC) for its financial support (NSC 100-2221-E-507-003) and National Applied Research Laboratories National Chip Implementation Center (CIC), Taiwan, for its technical support.

Disclosure statement

No potential conflict of interest was reported by the authors.