Silicon micromachined EBG resonator and two-pole filter with improved performance characteristics

A novel micromachined resonator at 45 GHz based on a defect in a periodic electromagnetic bandgap structure (EBG) and a two-pole Tchebyshev filter with 1.4% 0.15 dB equiripple bandwidth and 2.3 dB loss employing this resonator are presented in this letter. The periodic bandgap structure is realized on a 400 /spl mu/m thick high-resistivity silicon wafer using deep reactive ion etching techniques. The resonator and filter can be accessed via coplanar waveguide feeds.     

Direct-coupled resonator filters with improved selectivity

A method is outlined whereby a narrow-band direct-coupled resonator filter may be derived from an elliptic-function low-pass prototype. The construction and performance of a three-resonator waveguide cavity filter designed on this basis is described.     

两种改进的Fabry-Perot谐振器印刷天线

对各种Fabry-Perot谐振器印刷天线结构的辐射性能进行了详细比较,从而发展了两种改进结构:采用频率选择表面(FSS)为盖板、U形缝隙矩形贴片为辐射器、以及采用普通电导体或人工磁导体(AMC)为反射板,构成Fabry-Perot谐振器的印刷天线,实现了高增益、低旁瓣电平、高前后辐射比、较宽的阻抗与增益公共频带等性能,以及低轮廓结构.     

Switched-capacitor filters

A novel technique for building active filters using switched-capacitor (SC) circuits is proposed. Principles of operation, methods of control, analysis, and design of a typical SC filter are presented. To assess its effectiveness, the technique is used to control input current harmonics in a phase-controlled converter. It is shown that a wide range of harmonics can be controlled using a single filter     

Switched-capacitor DAC with analogue mismatch correction

A background calibration method for enhancing the accuracy and linearity of a switched-capacitor digital-to-analogue converter is described. The method can be used alone or in combination with mismatch shaping to achieve very high accuracy and linearity combined with high speed     

Switched-capacitor integrators with low finite-gain sensitivity

Compensated SC integrator stages are analysed and compared with respect to their sensitivities to finite amplifier gain effects. Simple single-stage amplifiers may be used in such circuits even in highly selective filtering applications. This may allow an extension of the present frequency range of SC circuits.     

一种片内集成飞电容的自适应开关电容DC-DC

提出一种电容片内集成、高效率升压模式的DC-DC电源管理芯片,较普通结构相比,文中提出的电路结构具有6组2×,3组3×,2组4×升压模型共11种工作模式,并具有低纹波等优点。通过MIM电容与积累型NMOS电容串联的方式,提高单位面积容值,使得总电容面积大幅减小。采用SMIC 0.18μm CMOS工艺,利用Cadence工具对电路进行仿真验证,所提出自适应开关电容升压电路,在输出电压为3 V时,其效率最高可达到83.6%。在开关频率为20 MHz时,输入电压范围为1~1.8 V,所需总片内集成电容总面积为900 μm×900 μm,输出电压纹波＜40 mV     

Switched-capacitor logarithmic DAC

An accurate. low-power, switched-capacitor (SC) digital-to-analogue converter (DAC) with exponential characteristics is presented. The design represents a significant improvement in performance and reduction in complexity over previously reported logarithmic DACs     

Switched-capacitor modulator circuits

Four switched-capacitor modulator circuits which make use of the system clock as the carrier are presented. the circuits are simple and fast: the output signals are sampled at twice the rate of the system clock. Two of the circuits are also offset-free. Experimental results are described; they demonstrate the functionality of the new schemes.<>     

一种应用开关电容分压的电源电压检测电路

提出了一种基于标准CMOS工艺的电压检测(Voltage Detector, VD)电路,具有高集成度、低功耗、检测点多档位可调节的特点。开关电容(Switched Capacitor, SC)电路仅需一个低频时钟即可提供准确的电源分压,在低功耗应用中可以有效替代传统电阻分压。在3.3V电源电压的MCU应用中,电压检测电路仅消耗几百nA的电流,对时钟变化不敏感（低频时钟频率变化范围4 kHz~40 kHz）,并且响应时间在一个时钟周期内     

Perturbation simulation for two-dimensional Josephson junctionarray with resonator structure

A numerical perturbation method to simulate phase-locking behavior for resonator structure-type Josephson junction arrays is introduced. Simulations are completed for one-dimensional parallel, one-dimensional series, and two-dimensional arrays showing new and interesting phenomena. The simulation results provide a clear view of the processes by which the Josephson junctions become mutually phase-locked. Optimum structure parameters for oscillator circuit designs are determined using these simulation results     

Switched-capacitor circuit design

Circuit design techniques are described for switched-capacitor filters, modulators, rectifiers, detectors, and oscillators. The applications of these circuits in telecommunications, speech processing, and other signal-processing systems are also briefly discussed.     

Switched-capacitor digital multiplier

A novel switched-capacitor circuit is proposed for digital multiplication. The principle of operation is based on digital-to-analogue conversion followed by successive-approximation analogue-to-digital conversion by means of binary-weighted capacitor arrays. An experimental circuit, implemented using discrete components, has confirmed the principle.     

同轴环形螺旋谐振腔设计分析

提出了一种适用于同轴环形放电结构气体激光器的环形螺旋谐振腔,并给出了理论分析。该谐振腔由一螺旋面反射镜和一球面反射镜构成,可充分提取激活区的能量并输出单束激光。该结构易于实现同轴环形放电激活区中的功率萃取。     

Switched-capacitor bandpass filter with quasi-continuous digitalQ-factor tunability

A second-order switched-capacitor (SC) bandpass filter with very wide Q-factor programmability range, is presented. Although the Q-factor is controlled by digitally varying the effective sampling frequency of an SC branch, quasi-continuous programmability is provided. Experimental results from a 0.8 μm CMOS integrated prototype demonstrate the versatility of the proposed technique     

Switched-capacitor integrator with reduced sensitivity to amplifier gain

A new switched-capacitor integrator with low sensitivity to finite amplifier gain is described. The circuit is simple, requiring very little extra chip area as compared to the uncompensated integrator. It is compared with previously proposed finite gain compensated switched-capacitor integrators.     

Switched-capacitor second-order noise-shaping coder

The rapid development of digital processing in the fields of instrumentation, control and communications has generated a good deal of research into simple, easily integrable, high-resolution A/D converters. Given the significant promise such converters offer for future application, a switched-capacitor version of a second-order noise-shaping coder intended for high-resolution conversion has been realised. This coder has been used successfully to produce a PCM signal.     

Switched-capacitor power electronics circuits

One of the main orientations in power electronics in the last decade has been the development of switching-mode converters without inductors and transformers. Light weight, small size and high power density are the result of using only switches and capacitors in the power stage of these converters. Thus, they serve as ideal power supplies for mobile electronic systems (e.g. cellular phones, personal digital assistants, and so forth). Switched-capacitor (SC) converters, with their large voltage conversion ratio, promise to be a response to such challenges of the 21st century as high-efficiency converters with low EMI emissions and the ability to realize steep step-down of the voltage (to 3 V or even a smaller supply voltage for integrated circuits) or steep step-up of the voltage for automotive industry or Internet services in the telecom industry. This paper is a tutorial of the main results in SC-converter research and design     

Switched-capacitor biquad with low influence of finite gains

The letter describes a switched-capacitor (SC) biquad which exhibits less effect of the finite gains on the Q-factor and centre frequency than other known biquads of this type. The properties of the circuit have been established by extensive simulation studies using a symbolic analysis program.     

An improved astigmatically compensated resonator for CW dye lasers

An improved resonator configuration for CW dye lasers is described, permitting minimum circular waist areas and compensation for comatic as well as astigmatic aberration.