Advances in Electrical and Computer Engineering (Oct 2009)
A Power-Efficient LC Quadrature VCO for RFID, Zigbee and Bluetooth Standards
Abstract
A multi-band CMOS LC Quadrature Voltage Control Oscillator (QVCO) with minimum power consumption is developed to meet the phase noise and frequency band requirements of RFID, Zigbee and Bluetooth standards. To accomplish the multi-band receiving architecture at low power consumption, current switching technique with optimized cross-coupled transistor sizes has been used. A comprehensive analysis of small signal model for complementary architecture including transistor noise sources and their effects on output phase noise amount has been discussed. Using extracted small signal model, coupled and coupling transistor sizes for minimum power consumption and the least achievable phase noise have been optimized. Designed QVCO has been implemented using TSMC 0.18um CMOS technology operating at 1.8V supply voltage. Proposed QVCO generates two separated frequency bands of 1.65-1.85GHz and 2.4-2.5GHz with phase noise of -125dBc/Hz at frequency offset of 3MHz. The total current drawn by QVCO is 7.5mA which makes the power consumption as low as 13.5mW.
