A fully integrated CMOS latched comparator is presented for use as a wake-up circuit that is attached to an RF energy harvester in a battery free wireless sensor network. The system consumes less than 36nA static current at 20°C and dissipates 2pJ of energy per conversion. The comparator comprises of...
An ultra low power crystal oscillator that provides a frequency reference for battery
powered timekeeping applications is presented. An amplitude control circuit is employed to ensure that minimum current is consumed. A subthreshold voltage regulator provides a supply voltage for the oscillator with minimum current consumption. The oscillator and regulator...
An enhanced swing differential Colpitts VCO (ESDC-VCO) dramatically improves
the swing of a Colpitts VCO by allowing the signal to swing below ground and above the
supply voltage. Fabricated in a 1P8M 0.13 um CMOS process, the ESDC-VCO operates
at 4.9GHz with a 0.475-V supply and consumes 2.7mW. The measured...
A fully integrated CMOS GPS receiver RF front end optimized for low power operation is presented. The system operates with a supply voltage down to 250 mV. A prototype has been fabricated in a 0.13μm CMOS process and includes a low voltage LNA, quadrature oscillators, and quadrature mixers. It exhibits...
In this thesis, the performance degradation of a phase-locked loop due to substrate noise is examined. A new analytical equivalent circuit model for substrate noise coupling is derived for a heavily doped silicon substrate. The model has been validated with measured data from a 0.35 μm CMOS process. Since the...
Low noise oscillators are universally needed in digital systems for clock generation and synchronization, and in radio-frequency communication front-ends for frequency up- and down-conversion. Noise in oscillators results in timing jitter, and limits the clock frequency of digital systems. In radio-frequency communication systems, phase noise in oscillators lowers the signal-to-noise...