ECCCII-Based Current-Mode Universal Filter with Orthogonal Control of w_o and Q

This paper presents a new current-mode current-controlled four-input five-output universal filter employing one current-controlled current conveyor (CCCII), one electronically tunable CCCII and two grounded capacitors. The proposed configuration provides lowpass, bandpass, highpass, bandstop and allpass current responses that taken from the high-output impedance terminals, which enable easy cascadability of the current-mode operation. The filter also offers both orthogonal and electronic controls of the natural frequency and the quality factor through adjusting the bias current of the CCCIIs. For realizing all the filter responses, the proposed filter does not require passive component-matching condition and both active and passive sensitivities are low. In addition, a new current-mode current-controlled single-input five-output universal filter can be achieved by using an additional multiple-output minus-type CCCII. The proposed filter is simulated using PSPICE simulations to confirm the theoretical analysis

Single-input Multiple-output Tunable Log-domain Current-mode Universal Filter

This paper describes the design of a current-mode single-input multiple-output (SIMO) universal filter based on the log-domain filtering concept. The circuit is a direct realization of a first-order differential equation for obtaining the lossy integrator circuit. Lossless integrators are realized by log-domain lossy integrators. The proposed filter comprises only two grounded capacitors and twenty-four transistors. This filter suits to operate in very high frequency (VHF) applications. The pole-frequency of the proposed filter can be controlled over five decade frequency range through bias currents. The pole-Q can be independently controlled with the pole-frequency. Non-ideal effects on the filter are studied in detail. A validated BJT model is used in the simulations operated by a single power supply, as low as 2.5 V. The simulation results using PSpice are included to confirm the good performances and are in agreement with the theory

Current-mode Biquadratic Universal Filter Design with Two Terminal Unity Gain Cells

A grounded parallel lossy active inductor and two current-mode (CM) universal filters are presented in this paper. All the circuits use two voltage followers (VFs) and a current follower (CF). The parallel lossy active inductor includes a grounded capacitor which is attractive in integrated circuit (IC) technology. The CM universal filters have one input and standard three outputs such as band-pass (BP), low-pass (LP) and high-pass (HP) responses. All-pass and notch outputs can be obtained by adding extra one CF. Suggested structures in this paper can be constructed with commercially available active devices such as AD844s. Non-ideal gain and intrinsic X-terminal parasitic resistor effects are examined. Several computer simulations with SPICE program and experimental results by employing AD844s are drawn to verify theoretical ones

High-Order Current-Mode and Transimpedance-Mode Universal Filters with Multiple-Inputs and Two-Outputs Using MOCCIIs

A high-order current-mode and transimpedance-mode universal filter with multiple-inputs and two-outputs based on multiple output second-generation current conveyors (MOCCIIs) is introduced. By choosing the input current terminals appropriately, the current-mode and transimpedance-mode lowpass, bandpass, highpass, notch or allpass filters can be obtained without component matching conditions. The proposed nth order universal filter requires (n+1) MOCCIIs, (n+1) resistors and n grounded capacitors. As examples, the first-order, biquadratic and third-order universal filters are given and compared with previous published works

The voltage-mode first order universal filter using single voltage differencing differential input buffered amplifier with electronic controllability

In this research contribution, the electronically tunable first-order universal filter employing a single voltage differencing differential input buffered amplifier (VD-DIBA) (constructed from two commercially available integrated circuit (IC): the operational transconductance amplifier, IC number LT1228, and the differential voltage input buffer, IC number AD830), one capacitor and two resistors. The features of the designed first order universal filter are as follows. Three voltage-mode first-order functions, low-pass (LP), all-pass (AP) and high-pass (HP) responses are given. The natural frequency (0) of the presented configuration can be electronically adjusted by setting the DC bias current. Moreover, the voltage gain of the LP and HP filters can be controllable. The phase responses of an AP configuration can be varied from 00 to −1800 and 1800 to 00. The power supply voltages were set at ±5 . Verification of the theoretically described performances of the introduced electronically tunable universal filter was proved by the PSpice simulation and experiment

Low-Voltage High-Linearity Wideband Current Differencing Transconductance Amplifier and Its Application on Current-Mode Active Filter

A low-voltage high-linearity wideband current differencing transconductance amplifier (CDTA) is presented in this paper. The CDTA consists of a current differencing circuit and a cross-coupling transconductance circuit. The PSPICE simulations of the proposed CDTA show a good performance: -3dB frequency bandwith is about 900 MHz, low power consumption is 2.48 mW, input current linear range is ±100 µA and low current-input resistance is less than 20 Ω, high current-output resistance is more than 3 MΩ. PSpice simulations for a current-mode universal filter and a proposed high-order filter are also conducted, and the results verify the validity of the proposed CDTA

Universal Filter Using Single Commercially Available IC: LT1228

In electrical and electronic engineering, the filter is very importance circuit. A voltage-mode three inputs single output second-order multifunction filter is presented in this paper. The proposed filter is based on RLC parallel circuit. The main active element is the commercially available IC from Linear Technology Inc, LT1228. The filter consists of single LT1228, single resistor and two capacitors. Five output second-order filter responses, namely band-pass (BP), band-stop (BS), high-pass (HP), low-pass (LP) and all-pass (AP) functions are achieved. Each output response can be selected without component matching condition and the requirement of double gain amplifier. The quality factor and natural frequency can be electronically controlled. PSpice simulation results suing macro model of LT1228 are in close agreement with the theory

The Lockheed alternate partial polarizer universal filter

A tunable birefringent filter using an alternate partial polarizer design has been built. The filter has a transmission of 38% in polarized light. Its full width at half maximum is .09A at 5500A. It is tunable from 4500 to 8500A by means of stepping motor actuated rotating half wave plates and polarizers. Wave length commands and thermal compensation commands are generated by a PPD 11/10 minicomputer. The alternate partial polarizer universal filter is compared with the universal birefringent filter and the design techniques, construction methods, and filter performance are discussed in some detail. Based on the experience of this filter some conclusions regarding the future of birefringent filters are elaborated

Universal three input and one output current-mode filter withoutexternal passive elements

A new current-mode universal filter is proposed. The filter uses only operational amplifiers and operational transconductance amplifiers (OTAs) and can realise lowpass, highpass, bandpass, notch and allpass responses without changing circuit topology. The parameters 0, 0/Q0, and the gain can be electronically tuned by adjusting the bias currents of the OTAs. The proposed circuit has low sensitivit

Biquad Based on a Generalized Divider Structure

The paper deals with the biquad based on a generalized divider structure. This principle can be considered as an effective way of universal filter and equalizers synthesis, which easily realizes any general transfer function. An attention is devoted to the derivation of optimum design conditions. As shown, these conditions strongly depend on the amplifier type used. The results obtained are illustrated by some design examples