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Summary: This paper introduces a second‐order voltage‐mode (VM) multiple‐input single‐output (MISO) universal filter and a second‐order current‐mode (CM) single‐input multiple‐output (SIMO) multifunction filter. The introduced VM MISO universal filter includes a single current feedback operational amplifier (CFOA) and a single voltage follower as active elements, while the introduced CM SIMO multifunction filter contains two CFOAs. Both introduced circuits are orthogonally controllable. In other words, the quality factors can be controlled through a single resistor without affecting the resonance frequencies. Both circuits have low sensitivities and no passive element‐matching conditions. The introduced VM MISO universal filter has a low output impedance. Moreover, to extract the output currents of the proposed CM SIMO from high impedance terminals, second‐generation current conveyor‐based version of the circuit is introduced. Simulations are made through the PSPICE program, where 0.13‐μm IBM CMOS technology parameters are utilized. DC supply voltages are selected as ±0.9 V. In the experiments, AD844s are used, and DC supply voltages are chosen as ±7.5 V. [ABSTRACT FROM AUTHOR]

First‐order generalized filter designs which simultaneously offer implementation of the low‐pass, high‐pass, and all‐pass filters basic functions with scaling of the associated time constant are presented in this work. These have been achieved thanks to the employment of the shadow filtering technique, which enables the utilization of a "hidden filter" for performing scaling of the time constant. The resulting filters offer also a high‐impedance input, and as the outputs are also taken from low‐impedance nodes, there is not any imposed restriction concerning their cascadability. The provided simulation and experimental results confirm the validity of the proposed concept. [ABSTRACT FROM AUTHOR]

Summary: A new second‐generation current conveyor‐based full‐wave rectifier (FWR) is proposed in this work. The proposed voltage‐mode FWR comprises a single active building block, four diodes, and three grounded resistors without needing any passive element matching problems. It does not suffer from any bias voltages and/or currents; therefore, it does not need extra circuitry. It can simultaneously provide positive and negative rectifications; thus, it is flexible. The proposed FWR has high input impedance; accordingly, it can be easily cascadable. Several simulations via the SPICE program and some experiments by using the AD844s are achieved. 0.18‐μm TSMC CMOS technology parameters are used in the simulations. [ABSTRACT FROM AUTHOR]

In this paper, a differential-input plus-type differential voltage current conveyor-based first-order universal filter is designed. This voltage-mode filter uses a grounded capacitor. In addition, it can provide all the noninverting and inverting first-order universal filter responses. The circuit provides high common-mode rejection ratio of about 76.5 dB. Nevertheless, it needs a single matching problem and comprises two floating resistors. Quadrature oscillator (QO) design is obtained using this filter as an application example. The designed filter and QO circuits are simulated through the SPICE program, and some experimental studies are carried out using AD844 ICs to verify the theory. [ABSTRACT FROM AUTHOR]

Summary: First‐order low pass and high pass inverse filter topologies, offering simplicity and independent adjustment of the gain and the characteristic frequency, are introduced in this work. These features are offered thanks to the terminals properties of the second generation voltage conveyor. In addition, possible applications of these types of filters are exploited. The behavior of a control system, where these filters are incorporated, is evaluated in both frequency and time‐domain using the Cadence IC design suite. [ABSTRACT FROM AUTHOR]