Ultrastable integrated CMOS oscillator

An ultrastable integrated CMOS oscillator capable of replacing crystal oscillators in many applications is presented. A stability of 7ppm°C^?1 has been obtained between ? 40 and + 100^°C by employing a novel thermal compensation scheme based on the thermal properties of MOS transistors operated near their point of zero temperature coefficient. The frequency and thermal stability can be precisely adjusted with two ordinary external resistors or with two on-chip resistors. The power supply sensitivity can be made nearly zero in specified voltage ranges determined during construction.     

An X-band integrated circuit FET oscillator with dielectric resonator stabilization

Experimental results are presented for the performance of a MIC common drain GaAs FET oscillator and are compared with the performance of the same oscillator stabilized by using a high Q. temperature compensated dielectric resonator made from barium nonatitanate. The unstabilized oscillator gave 85 mW of Rf power at an efficiency of 20%. whilst the compensated oscillator gave 46 mW of power at an efficiency of 12%. with a line width of only 0.3 MHz as measured at 60 dB below the peak. Over the temperature range 0 to 60°C the frequency of the stabilized oscillator changed only 5 MHz, compared t0 the 30 MHz change found in unstabilized oscillators. Mechanical tuning was easily achieved, and careful choice of coupling between the resonator and oscillator eliminated the hysteresis observed in the mode of oscillation of designs previously reported.     

Square-extensional mode single-crystal silicon micromechanical resonator for low-phase-noise oscillator applications

A micromechanical 13.1-MHz bulk acoustic mode silicon resonator having a high quality factor (Q=130 000) and high maximum drive level (P= 0.12 mW at the hysteresis limit) is demonstrated. The prototype resonator is fabricated of single-crystal silicon by reactive ion etching of a silicon-on-insulator wafer. A demonstration oscillator based on the new resonator shows single-sideband phase noise of -138 dBc/Hz at 1 kHz offset from the carrier.     

A 2.4-GHz silicon bipolar oscillator with integrated resonator

A 2.4 GHz fully-monolithic silicon-bipolar oscillator circuit implemented in a 12 GHz BiCMOS technology is presented. The integrated resonator circuit uses three different versions of a 2 nH multilevel inductor and a wideband capacitive transformer. The measured Q factor is 9.3 for the three-level inductor. An oscillator phase noise of -78 dBc/Hz is achieved at 20 kHz offset. The circuit dissipates 50 mW from a 3.6 V supply     

Fully CMOS integrated low voltage 100 MHz MEMS resonator

The development of a novel fully integrated microelectromechanical system (MEMS) for RF purposes is presented. It is composed of a paddle polysilicon micro-resonator electrostatically excited and a capacitive CMOS read-out amplifier. The micro-resonator is fabricated directly on a commercial CMOS technology, only requiring a wet etching process for the release of the resonant structure after the full CMOS integration. Electrical characterisation of the on-chip resonant device has been performed showing a resonance frequency near 100 MHz.     

Miniature high-Q double-spiral slot-line resonator filters

A new class of low insertion-loss miniaturized filters using slot-line resonators is proposed. Miniaturization is achieved by terminating the slot line with a double-spiral inductive termination at both ends. Using this miniaturized resonator, both positive and negative couplings may be realized, and therefore, both standard coupled-line and cross-coupled quasi-elliptic filters are realizable. The unloaded Q of these slot-line filters is considerably higher than that of miniaturized microstrip filters of comparable dimensions due to the inherent higher Q of the slot line. To demonstrate the validity of the design procedures and the performance characteristics, two different types of filters were fabricated and tested. One is a four-pole Chebyshev filter and the other is a quasi-elliptic filter where, in each case, the full-wave simulations show very good agreement with measurements.     

SOI-based radial-contour-mode micromechanical disk resonator

This paper reports a radial-contour-mode micromechanical disk resonator for radio frequency applications. This disk resonator with a gold plated layer as the electrodes,was prepared on a silicon-on-insulator wafer, which is supported by an anchor on another silicon wafer through Au-Au thermo-compression bonding.The gap between the disk and the surrounding gold electrodes is 100 nm.The radius of the disk is 20μm and the thickness is 4.5μm.In results,the resonator shows a resonant frequency of 143 MHz and a quality factor of 5600 in vacuum.     

基于SOI的径向体声学振动圆盘形微机械谐振器

本文报道了一种应用于射频领域的径向体声学振动模态的圆盘形微机械谐振器。谐振圆盘由SOI硅片制备,以金电镀层制作环绕电极。圆盘半径20um,厚4.5um,通过位于中心的锚点支撑,以金-金热压键合固定在另一个硅片上形成三维悬空结构。圆盘和环绕金电极之间的间隙为100nm。对制作的谐振器真空封装后进行测试,谐振频率为143MHz,品质因数为5600。     

SOl-based radial-contour-mode micromechanical disk resonator

This paper reports a radial-contour-mode micromechanical disk resonator for radio frequency applications.This disk resonator with a gold plated layer as the electrodes,was prepared on a silicon-on-insulator wafer,which is supported by an anchor on another silicon wafer through Au-Au thermo-compression bonding.The gap between the disk and the surrounding gold electrodes is 100 nm.The radius of the disk is 20 μm and the thickness is 4.5μm.In results,the resonator shows a resonant frequency of 143 MHz and a quality factor of 5600 in vacuum.     

A high-Q reconfigurable planar EBG cavity resonator

A reconfigurable planar electromagnetic bandgap (EBG) cavity resonator has been designed, fabricated, and tested. The resonator, based on a microstrip-coupled cavity constructed with periodic metallic post side walls, resonates at 10.60 GHz or 8.63 GHz, depending on the state of two rows of switchable post elements. Fabricated on 0.031 inch 5880 Duroid, the resonator exhibits Qs of 348 and 274 for the 10.60 GHz and 8.63 GHz resonances, respectively. In addition to the reasonably high Qs achievable with this design, the circuit utilizes standard printed circuit board (PCB) fabrication techniques and is 100% compatible with commercial PCB processes, enabling low-cost mass production     

An integrated wide-tunable sine oscillator

Describes a two-integrator sine oscillator which features independent control of frequency and damping and a lack of spurious responses and is integrable as a monolithic IC. The circuitry of this oscillator is discussed. The following experimental results were found: electronical, continuous tunability over four frequency decades, frequency shifting over at least one decade without amplitude deviation even with slow automatic volume control (AVC), about 1 percent distortion and an upper frequency limit of 200 kHz.     

RF oscillator implementation using integrated CMOS surface acoustic wave resonators

This work is a proof of concept that a monolithic CMOS surface acoustic wave (SAW) resonator can function as an RF oscillator. The design of the oscillator includes the measurement characteristics of the CMOS SAW resonator, its matching networks, and RF amplifier is described. The integrated SAW resonator, with its operating frequency controlled by the spacing of its transducers was fabricated using a combination of CMOS plus post-CMOS processes. Based on the operation and performance of the SAW resonators, an equivalent circuit model of the CMOS SAW resonator was developed. A series resonant oscillator design was simulated using Microwave Office^TM. The designed matching network improves both the insertion losses and the phase slope of the resonator, while the RF amplifier provides sufficient gain to ensure oscillation. Measurements conducted on the RF-CMOS SAW oscillator demonstrated oscillation at 600 MHz.     

Active-R realization of bilinear RL impedances and their applications in a high-Q parallel resonator and external capacitorless oscillator

Realization of bilinear RL impedances use only one operational amplifier (OA) and one or two resistors is proposed. These are based on the single-pole model of the OA. Applicabilities of these one-port active-R grounded inductances in a parallel capacitor tuned high-Qresonator and in a new external capacitorless sine-wave oscillator are also reported tosether with experimental verification.     

A high-Q low-dimensional resonator with electrically tunable frequency

A low-dimensional high-Q resonator has been proposed and its frequency-response characteristics have been investigated. The specified resonator features the frequency-response characteristics that are electrically tunable by using a semiconductor diode with variable capacitance.     

An integrated wide-band varactor-tuned Gunn oscillator

A report is made of a thin-film varactor-tuned Gunn effect oscillator in X band employing unencapsulated diodes. The Gunn device, which is an inverted mesa type, is mounted off the substrate on a copper header and this arrangement can dissipate 7 W without the Gunn device suffering thermal damage. The varactor is a beam-lead silicon p⁺nn⁺IMPATT diode connected in series with the Gunn device. A circulator is integrated with the oscillator to provide load isolation, and tuning ranges in excess of 2 GHz are reported. Good agreement exists between calculated and measured values of oscillator tuning range.     

Low-voltage low-power high-Q CMOS RF bandpass filter

Based on the gyrator-C inductor topology, a second-order bandpass filter can be realised by adding a series capacitor to the input port of the gyrator. high-Q second-, fourth- and sixth-order fully differential RF bandpass filters operating in the 2.4 GHz Industrial, Scientific and Medical (ISM) frequency band under a 2 V single power supply voltage with low-power dissipation are demonstrated     

An integrated CMOS telephone line adapter

A novel fully CMOS circuit for electronic telephone line adaption is described. In the on-hook state the circuit operates in micropower condition, dissipates only 5 A, and is capable of generating the supply voltage required for retention of data stored on external RAM. In the off-hook state the circuit is boosted into the normal operation mode and is able to drive external bipolar transistors to synthesize the line impedance. The dc and the ac line impedances are set with external components, thus permitting the fulfillment of different PTT specifications. The circuit also performs line signal extraction and transmission, both for voice and DTMF. The dc line voltage is monitored, and a supervision block generates a precise reset signal when the line voltage drops out. The circuit has been integrated in a CMOS P-well 3-m double-poly single-metal technology; the silicon area is 6 mm².     

Fully integrated low phase noise multi-band LC-tank voltage controlled oscillator with switched-capacitor resonator

This paper presents the design and implementation of a fully integrated low noise multi-band LC-tank voltage-controlled-oscillator(VCO).Multi-band operation is achieved by using switched-capacitor resonator.Additional three-bit binary weighted capacitor array is also used to extend frequency tuning range in each band.To lower phase noise,two noise filters are added and a linear varactor is adopted.Implemented in a 0.18 μm complementary-metal-oxide-semiconductor(CMOS) process,the VCO achieves a frequency tuning range covering 2.26～2.48 GHz,2.48～2.78 GHz,2.94～3.38 GHz,and 3.45～4.23 GHz while occupies a chip area of 0.52 mm2.With a 1.8 V power supply,it draws a current of 10.9 mA,10.6 mA,8.8 mA,and 6.2 mA from the lowest band to the highest band respectively.The measured phase noise is-109～-120 dBc/Hz and-121～-131 dBc/Hz at a 1 MHz and 2.5 MHz offset from the carrier,respectively.     

A novel high-Q LTCC stripline resonator for millimeter-wave applications

We have implemented a novel high-Q low temperature co-fired ceramic (LTCC) stripline resonator by including air cavities in the LTCC substrate for millimeter-wave applications. This new resonator presents Q-factor of 290 and total loss of 0.03 dB/mm at 34.8 GHz, and they are improved by 138% and 58%, respectively, compared to the conventional one. Its dielectric loss is analyzed as small as 0.0003 dB/mm at the resonant frequency, and that improved by a factor of 120 compared to the conventional one.     

A reduced-size silicon micromachined high-Q resonator at 5.7 GHz

This paper depicts the progress toward a novel high-quality-factor miniaturized resonator operating in the 5.6-5.8-GHz range. The design of the resonator is based on a micromachined cavity loaded with a high dielectric-constant material. Energy is coupled into the cavity from input and output microstrip lines via slots. Quality factors up to 640 are demonstrated on silicon planar structures with a volume of 177 mm/sup 3/. Further size reduction yields a volume of 24.5 mm/sup 3/ and quality factors ranging from 152 to 197, while keeping the resonator integration ability. Bonding techniques and the dielectric loss of the loading material are proven to be the limiting factors in achieving higher quality factors.