This paper presents a CMOS voltage controlled ring oscillator (VCO) with temperature compensation circuit suitable for low-cost and low-power MEMS gas sensor. This compensated ring oscillator is dedicated to Chopper Stabilized CMOS Amplifier (CHS-A). To operate at low frequency, a control voltage generated by a CMOS bandgap reference (BGR) is described and the measurement results of the fabrica...

In present work, improved designs for voltage controlled ring oscillators (VCO) using three transistors XNOR/XOR gates have been presented. Supply voltage has been varied from [1.8 1.2] V in proposed designs. In first method, the VCO design using three XNOR delay cells shows frequency variation of [1.900 0.964] GHz with [279.429 16.515] μW power consumption variation. VCO designed with five XNO...

Digital RF transceiver architectures increasingly require quadrature (I/Q) local oscillator sinusoid generation, where the phasenoise and power consumption of the quadrature voltage controlled oscillator (QVCO) have a significant impact on the system performance. The relevance of VCO power consumption becomes even more urgent due to the demand for implementations of ultra-low power short-range ...

Barium Strontium Titanate (BST) varactors utilized in a VCO demonstrate unique tuning characteristics compared to junction varactors. A 2.7 GHz microstrip line VCO operates in a tracking phaselock loop configured as an X4 frequency multiplier. BST oscillator tuning and the effect on loop dynamics is observed by the intentional design of an under damped system. Oscillator noise correction and pe...

| This paper presents a salient method to nd an optimal bandwidth for low noise phase-locked loop (PLL) applications by analyzing a discrete-time model of charge-pump PLLs based on ring oscillator VCOs. The analysis shows that the timing jitter of the PLL system depends on the jitter in the ring oscillator and an accumulation factor which is inversely proportional to the bandwidth of the PLL. F...

In this paper we present a CMOS quadrature ring oscillator operating at 0.5 V. Due to this very low voltage conditions, new project technique using the available terminal of the transistors (bulk) is used in order to reduce the threshold voltage of the transistors, thus improving the voltage headroom. The technique is applied in a conventional inverter-based ring oscillator with a feedback topo...

A novel noise-shifting differential Colpitts VCO is presented. It uses current switching to lower phase noise by cyclostationary noise alignment and improve the start-up condition. A design strategy is also devised to enhance the phase noise performance of quadrature coupled oscillators. Two integrated VCOs are presented as design examples.

A single stage source coupled Complementary Metal Oxide Semiconductor Voltage Controlled Oscillator (CMOS VCO) is designed in this paper. The design is implemented in Cadence environment with high oscillation frequency and low power consumption. This design is a single stage and it has low phase noise because author has reduced noise sources. Oscillation frequency of the designed VCO is ranges ...

Oscillators play a decisive role for electronic equipment in many fields – like communication, navigation or data processing. Especially oscillators are key building blocks in integrated transceivers for wired and wireless communication systems. In this context the study of fully integrated differential VCOs has received attention. In this paper we present an analytic analysis of the steady sta...

—In this paper, design and fabrication of a Ku-band voltage-controlled oscillator (VCO) using commercially available 0.18 μm SiGe BiCMOS technology is presented. To achieve the low phase noise, the VCO employs a gm-boosted configuration which is a combination of cross coupled VCO and balanced Colpitts VCO, and the VCO simultaneously achieves wide tuning range. The tested results show that the ...