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...
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...
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...
Delay insensitive asynchronous circuitry provides significant advantages with
respect to substrate noise due to localized switching. The differences between the
substrate noise from NULL Convention Logic (NCL) and traditional Clocked
Boolean Logic (CBL) are described and analyzed based on measured results. A test chip fabricated in the TSMC 0.25 um...
The dependence of the substrate resistance, R[subscript sub], for MOS transistor RF modeling on transistor biasing and layout is studied from device simulations and measurements. Though R[subscript sub] is found to be bias dependent, the error incurred by assuming a constant value equal to the DC resistance is not significant....
This work focusses on the modeling and the development of efficient coupled simulation techniques for MEMS based RF oscillators. High-level models for MEMS based varactors have been discussed and their accuracy issues are identified, based on comparisons with numerical simulations. A faster simulation approach based on the time-domain shooting method...