Symbolic analysis of networks containing current conveyors

Networks containing current conveyors can be analysed symbolically by the tree enumeration method. The procedures for incorporating inverting and noninverting current conveyors are different and involve operations on the voltage and current graphs.<>     

KHN-equivalent biquad using current conveyors

A new current-conveyor-based (CC) biquad, equivalent to the well known KHN circuit, is introduced. The proposed circuit employs exactly the same number (five) of CCs and resistors (six/seven) along with two grounded capacitors as in the two CC biquads recently reported by Soliman (see ibid., vol. 30, p. 2019-20, 1994). However, in contrast to Soliman's circuits, the proposed biquad offers several other advantages     

Kerwin-Huelsman-Newcomb circuit using current conveyors

Two equivalent circuits are generated using current conveyors to realise the same three transfer functions as in the Kerwin-Huelsman-Newcomb (KHN) biquad. Each circuit employs five current conveyors; two of them act as buffers. In both circuits, the two capacitors are grounded which is not the case in the KHN circuit     

Floating-impedance convertors using current conveyors

A floating-negative-impedance convertor and a generalised impedance convertor are described. The circuits use a practical realisation of the CCII+ type current conveyor, the design being based on a differential input/output transadmittance cell.     

Novel floating inductance using current conveyors

The letter presents a new ideal floating inductance using second generation current conveyors (CCIIs). The novel feature of this scheme is its realisation with all grounded passive components.     

Higher-order immittance functions using current conveyors

Two configurations for realizing higher-order series and parallel immittance functions using current conveyors are presented. The proposed circuits require only grounded resistors and capacitors. As examples of their applications, highpass and bandpass filters are given with simulation results.     

Wien bridge oscillators using current conveyors

Realization of oscillators with single resistor control based on the circuit techniques of the second generation current conveyors (CC II) utilizing the separability of the Wien RC one-ports that are generalized through appropriate insertion of two more resistors is considered. The relative frequency stability is shown to improve over the conventional op-amp Wien bridge versions.     

Floating ideal FDNR using current conveyors

A novel active current conveyor (CC II)-RC realisation of a floating admittance function Y(s) = s2D corresponding to an ideal FDNR element is reported. The scheme has the following advantages: (i) use of only two capacitors and a resistor; (ii) extremely low active sensitivities; (iii) single-resistor tunability of D; (iv) no design constraint involving component matching; (v) realisability of ideal FDNR even with nonideal CC II devices.     

Gyrator implementation with integrable current conveyors

An easily integrable circuit implementation of a current conveyor is presented. A low frequency high-Q gyrator realization employing current conveyor building blocks is discussed. Circuit design techniques to alleviate semiconductor device limitations are considered.     

New high accuracy CMOS current conveyors

In this paper, a new CMOS CCII⁺ is proposed. The circuit is characterized by high precision in voltage tracking and exhibits very low input resistance. An adaptive voltage offset cancellation methodology is introduced and then applied to the proposed circuit. As a result, a higher accuracy CCII⁺ is presented. For both circuits, the voltage offset cancellation is independent of the input current and voltage. To demonstrate the strength of the proposed architectures, fair comparisons with Liu and Yodprasit CCII realizations are held.     

Floating inductance simulation based on current conveyors

A basic floating inductance simulation circuit with grounded capacitance using only noninverting second-generation current conveyors as active elements is introduced. The circuit is modified by using current controlled conveyors, yielding electronically tunable inductances. Simulation results are also presented     

Constant bandwidth voltage amplification using current conveyors

Traditional feedback voltage amplifier formulations suffer from the restriction of a constant gain-bandwidth product, reducing the bandwidth dramatically at higher gains. A feedback voltage amplifier designed around a current conveyor or current amplifier completely overcomes this restriction and permits maximum bandwidth to be obtained for all values of gain.     

Voltage transfer function synthesis using current conveyors

A synthesis procedure for generating current conveyor active filters is presented, and a novel network which realises the general 2nd-order voltage transfer function is given.<>     

Impedance-controlled wideband active balun based on current conveyors

The first active power-split balun with controllable output impedance is proposed. Its operation is wideband, with good balance characteristics from DC to 3 GHz. It takes up 0.036 mm in a 0.35 mum SiGe BiCMOS technology and is the smallest balun ever observed. Its additional properties are: excellent and wideband overall S-parameter performance; highest linearity observed for a balun; and stability against temperature and process variations.     

Low-power CMOS switched-capacitor lowpass filter using current conveyors

A new approach is proposed to the design of high-order switched-capacitor LPFs of megahertz cutoff frequency for communications channel selection. It essentially uses current conveyors instead of op amps to achieve low power consumption. A fifth-order Chebyshev LPF with a 1-MHz cutoff frequency is thus synthesized and fabricated in a 0.35-μm CMOS technology. The LPF consumes less than 10 mW from a 3-V power supply and exhibits a third harmonic distortion better than ?54 dB in response to a 1-V sinusoidal input at the cutoff frequency. The rms noise voltage is at most 1.9 mV in a 2-MHz bandwidth.     

CMOS sinusoidal oscillator based on current-controlled current conveyors

A new realisation of a CMOS single resistance current-controlled current mode oscillator using active grounded resistances is described. A prototype has been realised in 0.8 /spl mu/m CMOS technology from AMS. Measurement results confirm oscillation over 10 MHz, low output distortion and wide tuning range.     

A new pipelined analog-to-digital converter using current conveyors

A new pipelined analog-to-digital converter (ADC) using second-generation current conveyor (CCII) is presented. Two main building blocks of the pipelined ADC, sample-and-hold (S/H) circuit and multiplying digital-to-analog converter (MDAC) are constructed of CCII instead of operational amplifier (OA). Experimental results show that the proposed CCII-based pipelined ADC can work at 12.5 MHz with a 7.3-bit resolution. The DNL is within −0.4 LSB and 0.4 LSB and INL is within −0.8 LSB and 0.8 LSB, respectively. The pipelined ADC is realized in TSMC 0.35 μm CMOS technology and consumes 29 mW under a 3.3 V power supply. The core size is 0.85×0.85 mm². Sing-Yen Wu received the M.S. degree in the Department of Electronic Engineering from National Taipei University of Technology, Taipei, Taiwan, in 2005. His current research interests include CMOS pipelined analog-to-digital converters and mixed-signal integrated circuit. Lu-Po Liao received the M.S. degree in the Department of Electronic Engineering from National Taipei University of Technology, Taipei, Taiwan, in 2003. His current research interests include analog integrated circuit design and mixed-signal integrated circuit design. Chia-Chun Tsai received the Ph.D. degrees in Electrical Engineering from National Taiwan University, Taipei, Taiwan, 1991. From 1989 to 2005, he served at the Department of Electronic Engineering, National Taipei University of Technology, Taipei, Taiwan. Since 2005 he has been with the Department of Computer Science and Information Engineering, Nanhua University, Chiayi, Taiwan, where he is a Full Professor. His current research interests include VLSI design automation and mixed-signal IC designs.     

Floating ideal FDNR using only two current conveyors

A new floating ideal FDNR realisation is presented which requires only two current conveyors (CC) as opposed to previously known schemes which require three or more CCs.