一种基于OTA和CCII实现的n阶低通滤波器

提出了用信号流图法设计n阶基于OTA（跨导运算放大器）和CCII（第二代电流传输器）电流模式低通滤波器的方法。该滤波器由具有双输出端的平衡滤波器和第二代电流传输器及接地电容构成。与同类电路比较，设计更简便，结构更简单，无源元件全部接地，易于集成。     

基于等价CCII结构的电压型/电流型转换方法

提出一种新的电压型电路转换为电流型电路方法。根据运算放大器及电流传输器(CCII)的原理给出了等价电流传输器结构。由运算放大器及其等价电流传输器结构的替换并结合伴随网络定理,可将电压型电路转换为电压操作信号和电流操作信号的电流型电路。通过SallenKey低通滤波电路说明该方法的正确性,并给出ADS仿真结果。     

基于电流传输器的正弦波振荡电路

本文给出了一种由单个第二代正相电流传输器（CCII＋）组成的电流模式正弦波振荡器电路。该振荡电路采用电流模组件AD844构成RC振荡器电路,与同类电路相比较,具有结构简单,频率调节方便等特点。文中给出了相应的实验结果。     

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     

基于复合管改进型电流镜的CCCⅡ电路

提出了一种新型的电流控制第二代电流传输器电路。该电路由6个复合管改进型电流镜和1个跨导线性环组成,该电路的电流传输精度远高于基于基本电流镜和级联电流镜实现的电流控制第二代电流传输器(CCCII)的电流传输精度。对电路原理进行了分析,并进行了硬件实验,实验结果表明频率在0～1.3MHz范围内能很好地满足CCCII的电流和电压特性关系,从而证明提出的电路是正确的。     

一种基于第二代电流传输器的积分器设计

介绍了一种基于低压、宽带、轨对轨、自偏置CMOS第二代电流传输器(CCII)的电流模式积分器电路,能广泛应用于无线通讯、射频等高频模拟电路中。通过采用0.18μm工艺参数,进行Hspice仿真,结果表明:电流传输器电压跟随的线性范围为-1.04～1.15 V,电流跟随的线性范围为-9.02～6.66 mA,iX/iZ的-3 dB带宽为1.6 GHz。输出信号的幅度以20dB/decade的斜率下降,相位在低于3 MHz的频段上保持在90°。     

一种新型低压高电流驱动能力的CMOS电流传输器

设计了一种电压和电流跟随能力强,低压驱动性能好的第二代电流传输器.采用SMIC 0.18 μm工艺,利用Spectre对整个电路进行了仿真.电源电压为1.8 V,输入级采用轨对轨的结构,有效地提高了信号的摆幅;输出级采用AB类推免输出方式,在降低电路功耗的同时,也提高了电流的驱动能力.通过采用MOS管与电容串联的补偿方式,有效地改善了CCII+的频率响应特性.仿真结果表明,该CCII+的-3 dB带宽达709 MHz,X端输入电阻低于100 Ω,电流驱动能力为0.05 mA-2.5 mA,电路功耗为140 μW.     

基于复合管改进型电流镜的CCCII电路

提出了一种新型的电流控制第二代电流传输器电路。该电路由6个复合营改进型电流镜和1个跨导线性环组成．该电路的电流传输精度远高于基于基本电流镜和级联电流镜实现的电流控制第二代电流传输器（CCCII）的电流传输精度。对电路原理进行了分析，并进行了硬件实验，实验结果表明频率在0-1．3MHz范围内能很好地满足CCCII的电流和电压特性关系，从而证明提出的电路是正确的。     

用信流图法设计n阶CCⅡ电流模式滤波器

提出了用信流图设计ｎ阶ＣＣⅡ（第二代电流传输器）电流模式低通滤波器的方法。该滤波器由具有双输出端的第二代电流传输器（ＣＣⅡ±）和同相第二代电流传输器（ＣＣⅡ＋）及接地ＲＣ元件构成。与同类电路［４］比较,设计更简便,结构更简单。ＲＣ元件全部接地,便于集成。     

电压控制的可线性调谐第二代电流传输器

由于可调谐第二代电流传输器调谐因子较窄以及电流控制的第二代电流传输器x端内部可控电阻rx受温度影响很大的问题,对可调谐的第二代电流传输器进行研究。引入2个电流增益可控的共源共栅电流镜放大电路和1个电压-电流转换器,提出了一种由电压控制的可线性调谐的第二代电流传输器,使电流增益能够通过外部电压之比连续可调谐。在3.3 V供电电源条件下,采用TSMC 0.35μm CMOS工艺参数对其进行Spectre模拟,结果表明,电压增益(vx/vy)及电流增益(ix/iz)的-3 dB带宽分别为400和101~412 MHz,电流增益调谐因子0≤k≤10.8,电路总谐波失真在3%以内,电路静态功耗为3.2 mW。     

A current conveyor-based relaxation oscillator as a versatile electronic interface for capacitive and resistive sensors

A new electronic interface circuit is presented. The circuit is built around a single plus-type second-generation current conveyor (CCII+) and can be used with resistive, capacitive and resistive-capacitive sensors. Experimental results are provided.     

An interfacing circuit for piezoresistive pressure sensors with frequency output

An interfacing circuit for piezoresistive pressure sensors based on the CMOS operational floating amplifier in a current conveyor configuration is presented. The main advantages of the proposed circuit include the use of only two piezoresistors with high common-mode rejection ratio, using an instrumentation amplifier based on a second-generation current conveyor (CCII) and temperature compensation. The circuit has frequency output proportional to the applied pressure with high linearity and temperature dependence less than 150ppm°C^?1. Experimental results, using the interfacing circuit and a commercial silicon pressure sensor, are included to demonstrate its performance.     

CMOS highly linear fully differential current conveyor

Design of a CMOS robust low-distortion fully differential second-generation current conveyor (CCII) is presented. The proposed circuit is essential to extend the use of the CCII-based circuits to high-performance VLSI applications. The design avoids using current mirror(s) in the signal path in order to minimise the distortion caused by mismatched mirroring transistors. The proposed circuit is implemented in a standard 0.5 /spl mu/m CMOS technology and its different characteristics are measured. Statistical measurement results show that the proposed fully differential CCII exhibits total harmonic distortion (THD) of -78.9 dB associated with less than 0.1 dB variation.     

Transformation of Voltage Mode Filter Circuit Based on Op-Amp to Circuit Based on CCII

In this paper, firstly we demonstrate the use of nodal admittance matrix to convert a low-pass band-pass filter based on operational amplifier (op-amp) to a circuit based on a second-generation current conveyor (CCII). This technique allows us to get eight presumptions of filter circuits. Secondly, we present a novel architecture circuit of CCII, which can operate at low supply voltage of 0.75 V. All simulations are performed by TSPICE models. The simulation results show that this circuit has a low impedance at terminal X (RX=1.01 ), a very high input impedance at terminal Y, and wide bandwidth current and voltage. The center frequency of the proposed filter is variable on the interval[157 kHz, 196 MHz].     

Implementation of reconfigurable nth-order filter based on CCII

Topologies for realizing voltage and current mode reconfigurable nth-order filters based on the second-generation current conveyor (CCII) are assessed. The most compatible structure for field-programmable analog array is identified. A CCII adopting active current division networks are utilized for implementing the proposed filter leading to wide control of its coefficients. Programmability characteristics are demonstrated through experimental results obtained from integrated circuit chips fabricated in a 0.18 μm CMOS process.     

Universal active current filters using single second-generation current conveyor

Two novel universal active current filters with a single second-generation current conveyor (CCII), which use fewer passive RC elements and have a larger quality factor than the previous two filters proposed by the author, are presented.<>     

All-pass filters based on CCII− and CCCII−

This paper proposes a first-order all-pass filter using one negative type second-generation current conveyor (CCII?), two resistors and a capacitor. From the proposed CCII? based filter, by replacing the CCII? and a resistor by a negative second-generation current-controlled conveyor (CCCII?) a new filter is developed which requires only one each of CCCII?, capacitor and resistor. The experimental and simulated results are found in good agreement with theoretical analysis. The circuits are also analyzed for non-ideal current conveyors to show that they still function as all-pass filters but with slight altered values of gain and phase.     

High input impedance voltage-mode universal biquadratic filter using two OTAs and one CCII

A three-input and single-output voltage-mode universal biquadratic filter with high input impedance, using only two operational transconductance amplifiers (OTAs), one plus-type second-generation current conveyor (CCII) and two capacitors, is presented. The proposed circuit can realize all the standard filter responses, that is, highpass, bandpass, lowpass, notch and allpass filters, from the same configuration. The proposed circuit has no requirements for component matching conditions.     

High-performance current conveyor implementation

Wideband precision current conveyor performance can be obtained by adapting an approach previously developed for current convertors. The proposed circuit implementation of a CCII+ current conveyor significantly exceeds the performance of all previous conveyor circuit formulations and is also more suitable for monolithic fabrication.     

CCII based more tunable voltage-mode all-pass filters and their quadrature oscillator applications

In this paper, two new voltage-mode (VM) first-order all-pass filters using single active element namely second-generation current conveyor (CCII) and a grounding capacitor are proposed. The first proposed filter employs a dual output CCII (DO-CCII) and the other one uses a modified minus type CCII (MCCII−). One of the main advantages of both configurations is their high input impedances; thus, both can be easily cascaded with other VM circuits. Additionally, the use of a grounded capacitor in both circuits provides suitability for integrated circuit (IC) fabrication process. However, both of the proposed circuits need a single passive component matching constraint. Non-ideality analysis is performed for the proposed circuits. Moreover, two quadrature oscillator applications of the proposed filters are given. The behavior of the filters is verified by SPICE simulations. Also, experimental tests using commercially available ICs (AD844s) are achieved for the second proposed configuration.