低阻抗聚苯胺铝电解电容器的制备与性能研究

采用化学法制备了可溶性导电聚苯胺,并通过浸渍法生成了铝电解电容器的阴极,经前后两次老练及调整中间的浸渍烘干工艺,制备出额定工作电压为DC6.3 V,标称电容量为1 000μF的固体高分子电解电容器。所制备电容器达到工业化生产的要求,其温度、频响和自愈特性都达到电脑主板等电子产品的应用需求。     

低阻抗聚苯胺铝电解电容器的研究

采用化学氧化法合成可溶性导电聚苯胺,作为电容器的阴极而取代传统的工作电解液阴极,研制了一种新型导电高分子固体铝电解电容器。其额定工作电压DC6.3V,标称电容量1000μF,tgδ≤0.036(100Hz,+20℃),漏电流IL≤20μA。此种电容器频率-阻抗特性优良,阻抗极低Z≤0.015?(100kHz,+20℃),并具有良好的温度特性和自愈特性。     

AMW型固体电容器

<正> 日本三洋电机公司最近研制成功最大电容量为47μF、额定工作电压为25V的卷绕式铝锰固体电容器。其特点如下:(1)最大电容量为47μF;(2)体积比该公司以往产品减小40％,能代替浸渍式钽电容器;(3)     

导电高分子固体铝电解电容器的研究

研制了一种被称为导电高分子固体铝电解电容器的新型电子元件。由于用化学聚合方法在电容器介质膜Al2O3表面形成导电聚吡咯(Polypyrrole)膜,作为电容器的阴极而取代传统的工作电解液阴极,因此新型电容器具有可靠性高,高频低阻抗,易于片式化等优点。研制的电容器的性能指标为:额定工作电压DC 6.3~16 V, 电容量范围2.2~33 mF,损耗角正切tgd≤0.06(120 Hz,+20℃),漏电流IL≤0.04 CV (或3 mA取大值),并具有良好的温度特性和频率阻抗特性。     

有机电解液MnO_2/AC混合电容器的研究

固相合成法制备了MnO2电极材料,以其为正极,活性炭(AC)电极为负极,组装了有机电解液MnO2/AC混合电容器。测试结果表明,在1 mol/L的有机电解液LiPF6/(DMC+EC)中,混合电容器的工作电压可达2.5 V,在不同的电流密度下,比容量为43.64～53.17 F/g,漏电流为0.08×10–3 A/cm2,经1 000次恒流充放电循环后,比容量衰减幅度约为8%。     

TDK铝电解电容器:紧凑型焊片式 纹波电流能力增强

正TDK公司近日发布了一款新的爱普科斯(EPCOS)焊片式系列铝电解电容器。新系列电容器的纹波电流能力比之前的爱普科斯(EPCOS)系列增强了多达25%,其中新B43642系列电容器尺寸紧凑:直径为22mm至35 mm,高度为25 mm至55 mm。该系列电容器额定电压范围为200 V DC至450 V     

PA-Cap聚合物电容器在模拟CPU电源中的应用

在计算机CPU的电源电路中,采用电解电容器作为电源的去耦电容。研究了CPU的负载高速变化时,三种类型电容器提供瞬时电流以稳定电源电压的情况。结果显示:PA-Cap聚合物片式叠层铝电解电容器(56μF)的Res为23mΩ,△V为–90mV,而220μF钽电容Res为73mΩ,△V为–172mV,1000μF液体铝电解电容Res为56mΩ,△V为–232mV。因此,PA-Cap聚合物电容器用在开关电源和数字电路中应用前景广阔。     

一种基于BJT工艺的电压反相电路设计

该文基于40 V耐压BJT工艺,利用电荷泵原理设计了一种DC/DC电压转换的电路.该电荷泵式转换电路使用电容器完成能量的传输与电压的转换,在实际电路中由一对开关电路与一个外部电容来实现对输入电压进行反相的电路功能.仿真结果表明,该电路在工作电压为8～20 V时,可提供-19～-7 V的输出,输出电流为10 mA,在1μ...     

浅析铝电解电容器的漏液问题

一、电解电容器的特点电解电容器的工作介质很薄,而且极板面积可以扩大,所以比率电容大,在工作电压低时尤为突出.如我厂军品上使用的63V(50V)-33000μF铝电解电容器,其比容达400μF/cm~3,这是其它电容器无法比拟的.特别是在滤波旁路方面铝电解电容器尚无竞争对手.由于电解电容器采用电解质做阴级,所以损耗较大,温度频率特性也差,采用液体电解质的电解电容器还容易发生漏液、干涸、老化甚至爆炸等问题.二、漏液问题与对策     

新品介绍

电容器高过载稳定性电容器由 Du San Industrial公司生产的 SMD片式电容器采用 1类介质瓷料 ,其电容量等随时间、电压和温度的变化可保持稳定的性能。这一优良特性使其可广泛应用于振荡器、滤波器和定时电路。NP0 - 40 3型 SMD片式电容器在 1k Hz、 1V (rms)、 2 5℃时的 tgδ小于 0 .1%。最大电流为 5 0 m A时 ,介电强度小于 2 .5倍工作电压。电容量偏差小于 10 p F。体积为 1.0 2 mm(长 )×0 .76 2 mm (宽 )× 0 .76 2 mm (高 )。Matsushita电子公司的片式瓷介电容器由 Matsushita公司生产的 ECK系列片式瓷介电容器比传统电容器的…     

用于功率变换的高击穿增强型AlGaN/GaN HEMTs

首次采用CF4等离子体技术实现可用于功率变换的增强性AlGaN/GaN功率器件。实验结果表明,当AlGaN/GaN器件经功率150W和时间150s等离子体轰击后,器件阈值电压从-4V被调制约为0.5V,表现为增强型。当漂移区LGD从5μm增加到15μm,器件的击穿电压从50V迅速增大到400V,电压增幅达350V。采用长度为3μm源场板结构将器件击穿电压明显地提高,击穿电压增加约为475V,且有着比硅基器件更低的比导通电阻,约为2.9mΩ.cm2。器件模拟结果表明,因源场板在远离栅边缘的漂移区中引入另一个电场强度为1.5MV/cm的电场,从而有效地释放了存在栅边缘的电场,将高达3MV/cm的电场减小至1MV/cm。微波测试结果表明,器件的特征频率fT和最大震荡频率fMAX随Vgs改变,正常工作时两参数均在千兆量级。栅宽为1mm的增强型功率管有较好的交直流和瞬态特性,正向电流约为90mA。故增强型AlGaN/GaN器件适合高压高频大功率变换的应用。     

Dual-bridge LLC-SRC with extended voltage range for deeply depleted PEV battery charging

This paper proposes a dual-bridge LLC series resonant converter with hybrid-rectifier for achieving extended charging voltage range of 50–420 V for on-board battery charger of plug-in electric vehicle for normal and deeply depleted battery charging. Depending upon the configuration of primary switching network and secondary rectifier, the proposed topology has three operating modes as half-bridge with bridge rectifier (HBBR), full-bridge with bridge rectifier (FBBR) and full-bridge with voltage doubler (FBVD). HBBR, FBBR and FBVD operating modes of converter achieve 50–125, 125–250 and 250–420 V voltage ranges, respectively. For voltage above 62 V, the converter operates below resonance frequency zero voltage switching region with narrow switching frequency range for soft commutation of secondary diodes and low turn-off current of MOSFETs to reduce switching losses. The proposed converter is simulated using MATLAB Simulink and a 1.5 kW laboratory prototype is also built to validate the operation of proposed topology. Simulation and experimental results show that the converter meets all the charging requirements for deeply depleted to fully charged battery using constant current-constant voltage charging method with fixed 400 V DC input and achieves 96.22% peak efficiency.     

纳米多孔硅的场致电子发射性能研究

对采用阳极氧化法及阴极还原表面处理技术制备的性能稳定的纳米多孔硅,用原子力显微镜(AFM)表征了其微观结构,多孔硅颗粒粒径在30 nm左右.室温条件下测试了多孔硅场电子发射的特性,结果表明,多孔硅具有很好的场致发光性能,在5 V/μm的电场下就可以产生场发射电流.多孔硅的开启电压在1 000 V左右,发射电流随着电压的增大而不断增大,发射电压在2 000 V以上.

Abstract：

Nanoscale porous silicon (PS) was prepared by anodic oxidation, cathode reduction and surface treatment technique. The porous silicon particles with the average diameter of about 30 nm were obtained by characterizing their microstructure with atomic force microscope (AFM). Electron field emission characteristics of porous silicon were investigated at room temperature. The resuhs demonstrate that porous silicon has favorable electroluminescence properties, and the field emission current can be generated only under the electric field of 5 V/ μm. And the turn - on voltage is about 1 000 V. With the increase of the offered voltage, the emission current is enhanced and the emission voltage is over 2 000 V.     

A precision low-power analog front end in 180 nm CMOS for wireless implantable capacitive pressure sensors

This paper presents a new capacitance to voltage analog-front end (AFE) designed in 180 nm CMOS technology for wireless implantable applications. This AFE consists of a Low-dropout regulator (LDO), bandgap reference (BGR), switched-capacitor (SC) sampler, SC op-amp and oscillator. The LDO regulates the wireless power supply coming from an off-chip rectifier and provides a stable and accurate DC voltage. Capacitance is converted to a discrete voltage by a SC sampling circuit and then amplified by a SC op-amp. Both of SC sampling and SC op amp circuits form a correlated double sampling scheme. This AFE is designed to sense a capacitance range from 6 pF to 7 pF (300–1000 mmHg) corresponding to a 0.68 V–1.07 V discrete output voltage with a sampling frequency of 1.63 KHz. This AFE has a sensitivity of 0.39 mV/fF, average power consumption of 201 μW and 3.25% accuracy operating over a 2.1 V–3.3 V rectified wireless supply voltage and −40 °C ~125 °C temperature range.     

A novel reconfigurable variable gain amplifier for a multi-mode multi-band receiver

This paper presents a novel approach for designing a reconfigurable variable gain amplifier(VGA) for the multi-mode multi-band receiver system RF front-end applications.The configuration,which is comprised of gain circuits,control circuit,DC offset cancellation circuit and mode switch circuit is proposed to save die area and power consumption with the function of multi-mode and multi-band through reusing.The VGA is realized in 0.18μm CMOS technology with 1.8 V power supply voltage providing a gain tuning...     

一种适用于MEMS麦克风的新型恒压电荷泵设计

实现了一种新型恒压输出电荷泵电路,通过选择合理的电荷泵结构能有效抑制反向电流及衬底电流,并通过一种负反馈稳压电路得到低纹波且不随电源电压变化的稳压输出,非常适用于MEMS麦克风。该电路采用MIXIC0.35μm标准CMOS工艺实现,测试结果表明该电路能自适应2.8～3.6V的电源电压变化,输出稳定的9V直流电压。     

片式高压多层瓷介电容器最新进展

片式高压多层瓷介电容器（ＭＬＣＣ）的研制生产水平已达额定直流电压０．５～２０ｋＶ。额定交流电压２２０～１１００Ｖ，标称电容量范围为：０．５ｐＦ～０．１５μＦ（Ｃ０Ｇ），４７ｐＦ～２．２μＦ（Ｘ７Ｒ）。产品技术标准尚未统一纳入国际标准体系。高压ＭＬ－ＣＣ在Ｖ－Ｃ、ＴＶＣ（温度、偏压、容量关系）、耐电压及电晕等性能和试验方法方面有特殊要求，设计制造技术有独到之处。高压ＭＬＣＣ的包装和使用须严格控制工艺过程。     

基于TL494的微型车载逆变器设计

针对汽车内部直流电源不能用于交流用电器的问题,设计了一款基于脉宽调制芯片TL494的微型车载逆变器。该逆变器采用DC-DC变换和DC-AC逆变两级结构,前级完成直流升压,后级选择脉宽调制（PWM）控制方式,将直流电压逆变为220V/50Hz的方波交流电。其中,DC-DC变换器先通过推挽逆变电路和高频变压器将12V变换为22V交变方波,再经快恢复二极管整流得到22V直流电。另外,该逆变器提供了一个标准USB接口,可以为具有USB接口的手机等设备充电。     

A robust low quiescent current power receiver for inductive power transmission in bio implants

In this paper, a robust low quiescent current complementary metal-oxide semiconductor (CMOS) power receiver for wireless power transmission is presented. This power receiver consists of three main parts including rectifier, switch capacitor DC–DC converter and low-dropout regulator (LDO) without output capacitor. The switch capacitor DC–DC converter has variable conversion ratios and synchronous controller that lets the DC–DC converter to switch among five different conversion ratios to prevent output voltage drop and LDO regulator efficiency reduction. For all ranges of output current (0–10 mA), the voltage regulator is compensated and is stable. Voltage regulator stabilisation does not need the off-chip capacitor. In addition, a novel adaptive biasing frequency compensation method for low dropout voltage regulator is proposed in this paper. This method provides essential minimum current for compensation and reduces the quiescent current more effectively. The power receiver was designed in a 180-nm industrial CMOS technology, and the voltage range of the input is from 0.8 to 2 V, while the voltage range of the output is from 1.2 to 1.75 V, with a maximum load current of 10 mA, the unregulated efficiency of 79.2%, and the regulated efficiency of 64.4%.