This letter presents an ultra low-jitter clock generator that employs an area-efficient LC-VCO. In order to fully utilize the area of the on-chip inductor, the loop filter of a phase locked loop (PLL) is located underneath the inductor. A prototype chip implemented in 0.13 μm CMOS process achieves 105 MHz to 225 MHz of clock frequency while consuming 4.2 mW from 1.2 V supply. The measured rms j...

Abstract This paper proposes a VCO topology in which the tail-current is adaptively modulated for enhancing the current efficiency. The adaptive modulation also ensures highly robust start-up over a wide range of PVT variation. The analysis also reveals that the tail-current modulation technique is also capable of alleviating the AM-PM conversion thereby extending the theoretical limit of the m...

This paper proposes a novel 8-phase VCO design implemented using Carbon Nanotube Field-Effect Transistors (CNTFETs). Carbon Nanotube is a fast growing and promising technology to replace Traditional MOSFETs. Its operation principles and device structure are similar to the conventional bulk CMOS, however it shows a great power delay improvement over bulk MOSFET due to its near-ballistic CNT tran...

A wide-tuning monolithic LC-tuned VCO is presented. The proposed VCO accomplishes wide tuning by utilizing binary weighted switched varactor combinations operating at minimum or maximum value, in addition to a linearly varying interpolation varactor. Measurements show 74% of tuning at a range of 1.56–2.71 GHz, with the phase noise ranging from 136 dBc/Hz to 108 dBc/Hz at 1 MHz offset. The VCO i...

BACKGROUND Chronic heart failure carries a poor prognosis. Cardiopulmonary exercise testing is useful in predicting survival. We set out to establish the prognostic value of peak VO(2)and VE/VCO(2)slope across a range of threshold values. METHOD AND RESULTS Three hundred and three consecutive patients with stable chronic heart failure underwent cardiopulmonary exercise testing between 1992 an...

Purpose – The demand for higher bandwidth has resulted in the development of mm-wave phased array systems. This paper explores a technique that could be used to feed the individual antennas in a mm-wave phased array system with the appropriate phase shifted signal, to achieve required directivity. It presents differential Colpitts oscillators at 5 GHz and 60 GHz that can provide differential ou...

The conductance catheter is widely used for the continuous measurement of the left ventricular (LV) pressure-volume loops. Cyclical change of the right ventricular (RV) volume may alter the parallel conductance volume, thereby affecting the LV mechanical parameters. Using 8 open-chest adult mongrel dogs, multiple LV pressure-volume loops were obtained by 2 methods: first with a vena cava occlus...

This paper includes Q-band VCO power injection-locked buffer for 77-GHz FM in 0.13-μm CMOS process. The center frequen VCO is 34.75-GHz with 1.6% tuning range. T noise performance shows -102.43 dBc/Hz frequency. The measured maximum single ou dBm and the ideal differential output power is dBm, owing to the injection-locked buffer w capability. The fabricated chip size is 0.51 × 0.1 consumption ...

In this paper, a high frequency dual PLL for a radio frequency transceiver is proposed. This new PLL architecture, which relaxes the trade off design constrains, consists in two PLL loops that drive the same VCO. The first loop has a high current charge pump that drives the high gain VCO side and is aimed to improve the settling time performance. The second loop has a low current charge pump th...

Voltage controlled oscillators are essential building blocks in communication systems and are used as local oscillators to up and down-convert signals in an RF mixer. Despite the continuous improvement in the state of the art of CMOS VCO’s, they still remain the most critical blocks of RF transceivers. The most important parameters of a VCO are phase noise, power consumption and frequency tunin...