高输出阻抗多功能电流模式双二阶滤波器

提出了一种基于多输出端差动差分电流传送器的多功能电流模式滤波器电路结构。该电路用三个多输出端差动差分电流传送器，五个或四个接地电阻和两个接地电容，同时实现了反相和，或同相带通和低通或带通和高通滤波响应特性。分析并模拟了所提出的滤波器的传递特性，PSPICE仿真结果表明，所提出的电路方案正确有效。电路具有灵敏度低，输出阻抗高，滤波器固有频率ωo和品质因数Q相互独立可调，多功能的优点，适于实现全集成连续时间滤波器。     

有源模拟带通滤波器的设计

根据有源模拟带通滤波器的特点,设计了一种工作在低频段且Q值在0～10之间的常用二阶模拟带通滤波器,比较了不同Q值及不同级数级联后的带通滤波器产生的通频带特性,并结合实际电路的效果评价,指出了在设计中应该注意的一些要点.     

差分式CMOS多功能电流模式滤波器

本文提出多端输出的CMOS电流加法器，在此基础上提出了新型差分式CMOS多功能电流模式滤波器的信号流图和电路。该滤波电路能同时产生二阶低通、带通、高通输出，并通过适当的连接能产生二阶带阻和全通滤波输出。对提出的滤波器截止频率为1MHz的电路进行了计算机PSPICE仿真。     

高通跨阻滤波器的设计

跨阻滤波器是将输入的电流信号转换成电压信号的同时完成信号滤波的一种新型滤波器。本文研究了高通跨阻滤波器的设计。根据传递函数中Q值的大小,分别给出了实现低Q值、中Q值和高Q值的跨阻高通滤波器电路、符号传递函数以及各种参数的符号表达式。高阶滤波器可以通过级联电压模式的滤波器二阶节电路得到。文中给出了设计实例。仿真结果验证了文中所提出的设计方法的正确性。     

差分式CMOS连续时间电流模式滤波器

提出了基地电流镜电路的差分式连续时间电流模式积分器，并用此积分器构成了全差分式连续时间电流模式低通及带通滤波器，分析并模拟了所提出的积分器及滤波器的特性，结果表明所提出了电路的具有结构简单，对称性好，失真小等优点，适于全集成。     

一种高Q值的TE01模介质滤波器的设计与实现

分析了介质谐振腔滤波器的设计方法和制造工艺,提出了一种用于小灵通无线基站的新型高Q值TE01模微波带通滤波器结构,并对其进行了仿真优化分析,最后制造出了六级式滤波器.通过对该滤波器的测量表明,这种滤波器性能良好,完全满足设计要求.     

可调谐N通道带通滤波器的设计

为了解决传统滤波器的中心频率不易调节、Q值低、带外抑制差和增益小等问题。本文设计了一种可调谐高Q值的增益提高型N通道带通滤波器,采用两路N通道差分结构和两个跨导放大器构成。差分结构消除偶次谐波,跨导放大器提高电路增益,片外变压器用作平衡-不平衡转换器,改善滤波器Q值并实现阻抗匹配。该滤波器在1.2 V供电电压下,采用TSMC 180 nm CMOS工艺,取N=4构成差分4通道滤波器。Cadence Spectre RF仿真结果显示,滤波器的增益大于8.5dB,中心频率可调范围为0.1～1 GHz,带内插入损耗S_(11)大于10 dB,带外IIP3大于10 dBm,噪声系数小于2.2 dB,在f_s=300 MHz处,带外抑制达到28 dB。该滤波器的高Q值、高可调谐和高性能使其在认知无线领域有着广泛的应用。     

新型高Q值U形缺陷地结构带阻滤波器

提出了一种新型的U形缺陷地结构(DGS)单元,该单元可以用来设计高Q值带阻滤波器。减小U形DGS结构两臂的槽宽及槽之间的距离,或在U形槽内加上贴片,可以增大Q值。最后用三个级联的U型DGS结构设计了一个高Q值的带阻滤波器,实验结果表明所设计的滤波器的Q值为35.3。     

一款应用于多频带的基于新型Cascode有源电感的高Q带通滤波器

设计了一款基于新型Cascode有源电感和有源负阻电路的二阶差分有源带通滤波器。新型有源电感和有源负阻电路的采用可实现在滤波器Q值不变的条件下对滤波器的中心频率进行调节。仿真结果表明,通过调节有源电感和有源负阻电路的偏置条件,可有效增大滤波器的Q值,且在保持Q值恒定在226的条件下中心频率的变化范围为0.2-3.7GHz。滤波器的以上特性使其能很好地应用于多频带的无线系统。     

基于差分器的开关电流高通梯形滤波器的设计

本文应用一种新型的双线性／前馈差分器来设计开关电流高通梯形滤波器，这种ＢＦＤ是用本文提出的ＳＩ模块，通用差分器构成，此ＧＤ具有多种差分功能，文中按Ｓ域频带变换和Ｚ域带变换分别介绍了两种不同的设计方法，还给出了Ｃｈｅｂｙｓｈｅｖ高通滤波器和椭圆高通滤波器设计的实例。     

New Fully‐Differential CMOS Second‐Generation Current Conveyer

This paper presents a new CMOS fully‐differential second‐generation current conveyor (FDCCII). The proposed FDCCII is based on a fully‐differential difference transconductor as an input stage and two class AB output stages. Besides the proposed FDCCII circuit operating at a supply voltage of ± 1.5 V, it has a total standby current of 380 µA. The applications of the FDCCII to realize a variable gain amplifier, fully‐differential integrator, and fully‐differential second‐order bandpass filter are given. The proposed FDCII and its applications are simulated using CMOS 0.35 µm technology.     

Second Order Band-Pass Filter Design Using Single CC-CDBA

Six new second order band-pass filter configurations using only a single current-controlled current differencing buffered amplifier (CC-CDBA) are proposed. Further, the proposed filters also have a minimum number of external electronic components. They realize current-mode, voltage-mode and transadmittance-mode filter characteristics. The quality factor and natural frequency can be adjusted electronically without changing the values of the passive components. The proposed filters use a minimum number of passive elements (two or three). There is no second order active filter structure which uses two passive components and one active component in the literature. The validity of the proposed filters is verified through PSpice simulations.     

采用单位增益放大器的高Q小电容分散的SC带通滤波器

本文提出了一种新的采用单位增益放大器的开关电容(SC)电路。该电路用于高Q带通滤波器实现时,可获得很小的电容分散,较同类的其它SC电路的电容分散有大幅度的减小。     

一种高输入阻抗单CCII电压模式滤波器

提出了一种实现高输入阻抗电压模式滤波器的新电路。该电路使用一个CCII(第二代电流传输器)和最少量的RC元件实现一阶低通、一阶高通及二阶带通滤波器。一阶滤波器仅含3个接地RC元件,二阶滤波器含4个RC元件,其中电容均接地。给出了电路的有源及无源灵敏度及计算机PSPICE仿真结果     

CMOS高频电流差分缓冲放大器

本文提出了一种利用修改的差分电流传输器(MDCC)与电压跟随器实现的全新高频CMOS差分电流缓冲放大器电路(CDBA).PSPICE仿真结果表明,在0～100MHz的频率范围内,提出的电路能很好地满足CDBA的端口特性.作为应用,实现了二阶电流模式多功能滤波器,并对他们进行了仿真.     

New topology for implementing bandpass,bandstop and allpass filters with CFAs

In this brief, a new filter topology based on current feedback amplifiers is presented and compared with its operational amplifier counterpart. The circuits arising from the new topology have the important advantage that access to the Z node of the current feedback amplifier is not required, as is the case with many existing current feedback amplifier filter circuits. The operation and requirements for each of the filters are described. Theoretical results and circuit limitations are discussed and verified with experimental results. In one experiment a bandpass filter with a calculated Q and centre frequency of 20 and 158.53 kHz, respectively was built using the OPA2607 dual CFAs IC. Measured results yielded a Q of 20.153 at a centre frequency of 148.62 kHz showing close agreement with theory.     

Low‐Voltage CMOS Current Feedback Operational Amplifier and Its Application

A novel low‐voltage CMOS current feedback operational amplifier (CFOA) is presented. This realization nearly allows rail‐to‐rail input/output operations. Also, it provides high driving current capabilities. The CFOA operates at supply voltages of ±0.75 V with a total standby current of 304 µA. The circuit exhibits a bandwidth better than 120 MHz and a current drive capability of ±1 mA. An application of the CFOA to realize a new all‐pass filter is given. PSpice simulation results using 0.25 µm CMOS technology parameters for the proposed CFOA and its application are given.     

High Input Impedance Voltage-Mode Universal Biquadratic Filter with Three Inputs Using DDCCs

A new high input impedance voltage-mode universal biquadratic filter with three input terminals and five output terminals is presented. The proposed circuit uses three plus-type differential difference current conveyors, two grounded resistors and two grounded capacitors. The proposed circuit can realize all the standard filter functions: lowpass, bandpass, highpass, notch and allpass, without component matching conditions. The proposed circuit offers the features of high input impedance, low active and passive sensitivities and the use of only grounded resistors and capacitors.     

Band-pass filter with high quality factor based on current differencing transconductance amplifier and current amplifier

This paper presents second order band-pass filter with high quality factor. Its high quality factor is provided by feedback circuit. The used second order filter is modified so that filters outputs through capacitor can be obtained to high impedance output. Thereby, there is no need the extra active element to obtain filter outputs. Also, the output stage of current differencing transconductance amplifier have only X− terminals instead of X+ and X− terminals. Furthermore, the quality factor of the band-pass filter with feedback circuit is increased by feedback gain consisting of only four transistors. Besides, to examine effects of parasitic elements, non-ideal and sensitivity, the overall structure is investigated deeply. Working conditions and boundaries of the overall structure is also defined. The simulation demonstrates good agreement between the theoretical expectations and simulation results.     

Current-mode continuous-time fully-integrated universal filterusing CDBAs

The authors propose a new, fully-integrated universal filter using a current differencing buffered amplifier, a recently introduced active element. It has been shown that the use of the current differencing buffered amplifier in fully-integrated filter design is attractive in that it simplifies the implementation and makes possible the use of a minimum number of grounded capacitors, compared to those using second generation current conveyers and current feedback amplifiers