硅微机械悬浮结构电感的设计与制作工艺研究

本文系统分析了影响平面螺旋电感Q值的主要因素,并制作出一种应用于射频通信的硅微机械悬浮结构电感.在考虑趋肤效应、涡流损耗等高频电磁场效应对电感Q值的影响后,获得了微机械电感的简化电学模型,得到了具有较高Q值电感的优化结构.在制作硅微机械电感的工艺过程中,采用多孔硅作为牺牲层材料,将螺旋结构铝线圈制作在二氧化硅薄膜上,在使用添加了硅粉和过硫酸铵的TMAH溶液释放牺牲层之后,得到设计值为4nH的悬浮结构微机械平面螺旋电感.实验结果证明,整个工艺流程可靠,并与CMOS工艺兼容.     

New canonic lossy inductor using a single CDBA and its application

A new lossy inductor (parallel R-L type) using single current differencing buffered amplifier (CDBA) is presented, which employs only two resistors and a grounded capacitor. The proposed lossy inductor is shown to be useful in realizing an oscillator circuit, which provides quadrature voltage outputs using only two CDBAs, three resistors and two grounded capacitors and offers independent control on condition of oscillation and frequency of oscillation up to a frequency of 61 MHz. Detailed non-ideal analysis including single-pole model for voltage and current gain has also been carried out. SPICE simulation results and experimental results based upon the CDBA constructed from commercially available IC AD844 have been included which confirm the practical workability of the proposed lossy inductor and quadrature oscillator circuit.     

一种硅衬底镂空结构的圆形射频微电感

利用MEMS工艺以及硅的湿法刻蚀工艺制作了一种硅衬底镂空结构的圆形射频微电感，并研究了硅衬底背面减薄对射频微电感性能的影响，结果表明：微电感硅衬底经过局部刻蚀减薄后其自谐振频率上升，电感量的频率稳定性提高，而其最大Q值下降。     

微波单片集成有源电感

本文介绍了一种由砷化镓单片集成电路工艺实现的Q值相对较高的微波有源电感的新型结构,其电路原理图由三个微波场效应晶体管和一个电容组成.这种微波有源电感具有工作频率高,电感值不受晶片大小的限制,并且具有可受直流偏压控制的特点,在微波电路微型化方面具有较高的实用价值.     

A 1.0 V differential VCO in 0.13 μm CMOS technology

A differential complementary LC voltage controlled oscillator(VCO) with high Q on-chip inductor is presented.The parallel resonator of the VCO consists of inversion-mode MOS(I-MOS) capacitors and an on-chip inductor.The resonator Q factor is mainly limited by the on-chip inductor.It is optimized by designing a single turn inductor that has a simulated Q factor of about 35 at 6 GHz.The proposed VCO is implemented in the SMIC 0.13μm 1P8M MMRF CMOS process,and the chip area is 1.0×0.8 mm~2.The free-running frequency is from 5.73 to 6.35 GHz.When oscillating at 6.35 GHz,the current consumption is 2.55 mA from a supply voltage of 1.0 V and the measured phase noise at 1 MHz offset is -120.14 dBc/Hz.The figure of merit of the proposed VCO is -192.13 dBc/Hz.     

A novel voltage sensorless control technique for a bidirectional AC/DC converter

A novel voltage sensorless control technique for a bidirectional AC/DC converter is presented. Only a single current sensor that measures the inductor current is needed in the whole system. The sensed inductor current is used for two functions. The first one is for shaping the current waveform at the AC side and the second one is for deriving the inductor voltage by determining the rate of change of the inductor current. The AC-side and DC-side voltages, which are used for AC current synchronization and DC voltage regulation, respectively, are obtained by extracting the envelopes of the derived inductor voltage. Apart from reducing the number of sensing elements, the proposed method has additional advantages of: (1) inherent electrical isolation and reducing noise coupling between the power circuit and the controller; (2) wide operating range. Design criteria for the differentiator and the envelope detector circuit has been described. The applicability of the proposed method is verified with the experimental results of a laboratory prototype.     

A novel method to achieve zero-voltage regulation in buck converter

The function control law for a buck converter is derived to achieve zero voltage regulation of the output voltage. A new method to retrieve the low frequency component of the inductor voltage is proposed and analyzed. The stability of the closed loop system using a proportional and differential controller is analyzed. The effect of the supply voltage and load current disturbance is also studied. The analysis, computer simulation by PSPICE and experimental results illustrate that excellent performance can be achieved by the function control law     

A 0.13μm CMOS △∑ fractional-N frequency synthesizer for WLAN transceivers

A fractional-N frequency synthesizer fabricated in a 0.13 μm CMOS technology is presented for the application of IEEE 802.11 b/g wireless local area network (WLAN) transceivers.A monolithic LC voltage controlled oscillator (VCO) is implemented with an on-chip symmetric inductor.The fractional-N frequency divider consists of a pulse swallow frequency divider and a 3rd-order multistage noise shaping (MASH) △ ∑ modulator with noise-shaped dithering techniques.Measurement results show that in all channels,phase noise of the synthesizer achieves -93 dBc/Hz and -118 dBc/Hz in band and out of band respectively with a phase-frequency detector (PFD) frequency of 20 MHz and a loop bandwidth of 100 kHz.The integrated RMS phase error is no more than 0.8°.The proposed synthesizer consumes 8.4 mW from a 1.2 V supply and occupies an area of 0.86 mm2.     

5-GHz Low Phase-Noise CMOS VCO Integrated With a Micromachined Switchable Differential Inductor

A 5-GHz CMOS voltage-controlled oscillator (VCO) integrated with a micromachined switchable differential inductor is reported in a 0.18 mum radio frequency-CMOS-based microelectromechanical system technology. The power consumption of the core is about 8 mW at the supply voltage of 1.8 V. A total tuning range of 470 MHz (from 5.13 GHz to 5.60 GHz) is achieved as the tuning voltage ranging from 0 V to 1.8 V. In the practical tuning range, the measured phase noise performances at 1 MHz offset are less than -125 dBc/Hz and -126 dBc/Hz when the inductor switch is turned on and off, respectively. The figure-of-merit is better than -190 dB. When compared with a contrast VCO circuit that utilizes a standard switchable differential inductor, this oscillator reaches a phase noise improvement of around 3 dB as the switch is turned on. Around 1-dB on-off phase noise difference can be achievable.     

集成双层平面电感的单片DC/DC转换器设计

采用0.35μm标准CMOS工艺设计了3.3V/1.5V单片低压Buck转换器,开关频率为150MHz.本文采用了电压型脉宽调制的反馈控制模式,克服了频率提高所带来的转换器系统不稳定问题.对双层平面螺旋电感进行了设计与优化,获得品质因数2.6,电感值28nH的双层平面电感.模拟结果表明,对应于不同输入电压或不同负载,转换器系统工作稳定,输入调整率-40dB,输出调整率-60dB.输出电压纹波平均值可以控制在额定值75mV,转换效率71%.     

A new family of isolated converters that uses the magnetizinginductance of the transformer to achieve zero-voltage switching

A new family of isolated, zero voltage switched power converters which utilizes the magnetizing inductance of the transformer to achieve zero voltage turn-on of the primary switches is proposed. By employing saturable inductor(s) on the secondary side, soft turn-off of the output rectifier(s) is obtained with a minimum circulating energy flowing through the power converter. The proposed converters can operate either with a variable or a constant switching frequency. A complete DC analysis and design guidelines for the half-bridge topology are described, and the performance of a 100 W experimental power converter is presented     

A 5 GHz CMOS frequency synthesizer with novel phase-switching prescaler and high-Q LC-VCO

A phase-locked loop(PLL) frequency synthesizer with a novel phase-switching prescaler and a high-Q LC voltage controlled oscillator(VCO) is presented.The phase-switching prescaler with a novel modulus control mechanism is much more robust on process variations.The Q factor of the inductor,I-MOS capacitors and varactors in the VCO are optimized.The proposed frequency synthesizer was fabricated by SMIC 0.13μm 1P8M MMRF CMOS technology with a chip area of 1150×2500μm~2.When locking at 5 GHz,the current consumption is 15 mA from a supply voltage of 1.2 V and the measured phase noise at a 1 MHz offset is -122.45 dBc/Hz.     

A 0.35-/spl mu/m CMOS 2-GHz VCO in wafer-level package

This letter presents a complementary metal oxide semiconductor (CMOS) voltage-controlled oscillator (VCO) with a high-Q inductor in a wafer-level package for the LC-resonator. The on-chip inductor is implemented using the redistribution metal layer of the wafer-level package (WLP), and therefore it is called a WLP inductor. Using the thick passivation and copper metallization, the WLP inductor has high quality-factor (Q-factor). A 2-nH inductor exhibits a Q-factor of 8 at 2 GHz. The center frequency of the VCO is 2.16 GHz with a tuning range of 385 MHz (18%). The minimum phase noise is measured to be -120.2 dBc/Hz at an offset frequency of 600 kHz. The dc power consumed by the VCO-core is 1.87 mW with a supply voltage of 1.7 V and a current of 1.1 mA. The output power with a 50-/spl Omega/ load is -12.5/spl plusmn/1.3 dBm throughout the whole tuning range. From the best of our knowledge, compared with recently published 2-GHz-band 0.35 /spl mu/m CMOS VCOs in the literature, the VCO in this work shows the lowest power consumption and the best figure-of-merit.     

Wide tuning-range CMOS VCO based on a tunable active inductor

In this paper, a wide tuning-range CMOS voltage-controlled oscillator (VCO) with high output power using an active inductor circuit is presented. In this VCO design, the coarse frequency is achieved by tuning the integrated active inductor. The circuit has been simulated using a 0.18-µm CMOS fabrication process and presents output frequency range from 100 MHz to 2.5 GHz, resulting in a tuning range of 96%. The phase noise is –85 dBc/Hz at a 1 MHz frequency offset. The output power is from –3 dBm at 2.55 GHz to +14 dBm at 167 MHz. The active inductor power dissipation is 6.5 mW and the total power consumption is 16.27 mW when operating on a 1.8 V supply voltage. By comparing this active inductor architecture VCO with general VCO topology, the result shows that this topology, which employs the proposed active inductor, produces a better performance.     

High Performance Inductors on CMOS-Grade Trenched Silicon Substrate

This paper reports on a new implementation of high-quality factor copper inductors on CMOS-grade silicon substrates (p = 10-20 Omega ldr cm) using a CMOS-compatible process. A low-temperature fabrication sequence (<300degC) is used to reduce the loss in silicon at RF frequencies by trenching the silicon substrate. The high aspect-ratio (30:1) trenches are subsequently bridged over or refilled with a low-loss dielectric to close the open areas and create a rigid low-loss island, referred to as Trenched Si Island. This method does not require air suspension of the inductors, resulting in mechanically-robust structures that are compatible with any packaging technology. A one-turn 0.8 nH inductor fabricated on a Trenched Silicon Island exhibits a very high peak quality factor of 71 at 8.75 GHz with a self-resonant frequency larger than 15 GHz.     

On-chip self-calibration system for CMOS active inductor band pass filter

A calibration system aiming for automatically correcting the effect of process variation on performance of on-chip Active Inductor Band Pass Filter (AIBPF) is presented. The benefit of using active inductors to build on-chip band pass filter is less chip area consumption and the tunability of center frequency compared to designs employing passive inductors. However, the fatal drawback of active inductor is performance degradation caused by process variation generated during chip fabrication. The proposed calibration system has the ability to detect process variation and adjust the AIBPF center frequency back to the designed 5.2 GHz by compensating the bias voltage. Simulation results show this calibration system can significantly improve the yield of circuits employing AIBPFs.     

Integrated ZVS DC–DC converter with continuous input current and high voltage gain

An integrated zero-voltage-switching (ZVS) DC–DC converter with continuous input current and high voltage gain is proposed. The proposed converter can operate with soft switching, a continuous inductor current and fixed switching frequency. The voltage stress of the power switches is relatively low compared to the output voltage. Moreover, soft-switching characteristic of the proposed converter reduces switching loss of active power switches and raise the conversion efficiency. The reverse-recovery problem of output rectifiers is also alleviated by controlling the current changing rates of diodes with the use of the leakage inductance of a coupled inductor. The operation and performance of the proposed DC–DC converter were verified on an 115?W experimental prototype operating at 100?kHz.     

A Low-Noise X-Band Parametric Amplifier Using a Silicon Mesa Diode

This paper summarizes a cooperative effort to develop silicon mesa variable-capacitance diodes and to evaluate their potential for achieving low-noise amplification in the high microwave frequency range. Cutoff frequencies of about 70 kMc at zero-bias voltage (corresponding to 140 kMc at maximum reverse bias voltage) with a total permissible voltage swing in excess of 5 volts have been obtained. A versatile degenerate X-band parametric amplifier was developed which, when used in conjunction with these silicon mesa diodes, achieved a radiometer noise temperature of 130°K at 8.5 kMc with a 50-Mc bandwidth at 17-db gain. The measured performance of the diode (figure of merit) is compared with the first-order theory in an operating radar system. The over-all performance of the amplifier improved the observed system sensitivity by 6 db.     

Analysis of voltage doubler ZVS converter

A novel zero voltage switching (ZVS) isolated converter is presented. The output voltage doubler is used on the output side to achieve the boost type of voltage conversion ratio. Active-clamping technique is adopted to realise the ZVS turn-on of all switches. The proposed circuit has no large output inductor such that the adopted circuit has a simpler structure, lower cost and no effective duty loss. Finally experimental results based on a 300 W prototype are provided to verify the effectiveness of the proposed converter.