Title :
A capacitively-coupled 5GHz CMOS LC oscillator with bias tuning capability
Author :
Vatti, Sofia ; Papavassiliou, Christos
Author_Institution :
Technol. & Med. Exhibition Road, London
Abstract :
A novel bias and tuning scheme for capacitively cross-coupled inductance-capacitance (LC) oscillators is presented. This scheme allows more flexibility in defining the operating point of the cross-coupled transistors, together with wide frequency tunability. A capacitively coupled LC oscillator at 5 GHz has been designed in CMOS UMC 0.18 mum technology. The bias network is realized with an all-transistor voltage reference. The oscillator is tunable in the 5 GHz-9 GHz frequency range. Phase noise performance is maintained over the entire frequency range, with -58 dBc/Hz at 100 kHz offset and -116 dBc/Hz at 1 MHz.
Keywords :
circuit tuning; microwave oscillators; phase noise; transistors; all-transistor voltage reference; bias tuning capability; cross-coupled inductance-capacitance oscillators; cross-coupled transistors; frequency 100 kHz; frequency 5 GHz to 9 GHz; phase noise performance; wide frequency tunability; CMOS technology; Circuit noise; Frequency; Impedance; MOSFETs; Oscillators; Phase noise; Switches; Tuning; Voltage;
Conference_Titel :
Circuits and Systems, 2007. MWSCAS 2007. 50th Midwest Symposium on
Conference_Location :
Montreal, Que.
Print_ISBN :
978-1-4244-1175-7
Electronic_ISBN :
1548-3746
DOI :
10.1109/MWSCAS.2007.4488633