A simple sinusoidal quadrature oscillator using a single active element

This study describes a simple design for a single active element sinusoidal oscillator with a quadrature signal. A current conveyor transconductance amplifier (CCTA), a single resistor, and two grounded capacitors are used in the first circuit. The second circuit is improved by using a current-controlled current conveyor transconductance amplifier (CCCCTA) and two grounded capacitors without a passive resistor, which means the grounded capacitor is suitably implemented for the IC fabrication. The oscillation condition and frequency of both circuits can be controlled using the same method that concurrently adjusts the DC bias current and the resistance as well as the oscillation frequency can be independently adjusted by capacitances. The CCTA is achieved by cascading the integrated circuits (IC) AD844 and LM13700, made by Analog Devices Corporation and Texas Instruments, respectively, which are available for commercial purchase. The sinusoidal quadrature signals in the time-domain and frequency-domain can be shown with computer simulations and the results of experiments. The Monte Carlo Analysis is also utilized to examine the oscillation frequency with the influence of passive element tolerance errors. The predicted oscillation frequency has a standard variation of about 20.04 kHz, with a maximum frequency of approximately 346.89 kHz and a minimum frequency of approximately 259.09 kHz. In addition, the mean and median frequencies are 296.10 and 293.98 kHz, respectively. The results of this study indicate that computer simulation and experiment are similar to a theoretical analysis, making them suiTable for use in the teaching of electrical and electronic engineerin

A fully balanced first order high-pass filter

The topic of this article is the design of a fully balanced first-order high-pass filter and its two circuits. The first circuit is a fully balanced current-tunability first-order high-pass filter consisting of four NPN transistors and a single capacitor, which is a simple design and quite compact. The pole frequency can be adjusted with a bias current. The results of the first circuit shows the phase and gain responses, the phase and gain responses when adjusted with a bias current, the time-domain response, and the harmonic spectrum. However, this circuit found a flaw in the temperature that affects the pole frequency, and total harmonic distortion is relatively high. Therefore, the second circuit improves defects by the CAPRIO technique to reduce the total harmonic distortion, and the resistors in the circuit are added to the design to replace the resistance and the effect of temperature on the properties of the transistor. This circuit consists of four NPN transistors, four resistors, and a single capacitor. The resistors in this circuit can be adjusted to change the pole frequency and voltage gain. The results of the second circuit show the gain and phase responses of the proposed circuits, the phase and gain responses when adjusted to the value of the resistor, the phase and gain responses at various temperatures, as well as their time-domain responses and total harmonic signal distortion. The all-pass filter is also made using the filter introduced in the second circuit because of its voltage gain-adjustable property. So, if the suggested circuit is constructed in combination with a buffer circuit to make it feasible to function as an all-pass filter, the result will be an all-pass filter. In accordance with the results of this study, we have introduced a design for a high-pass filter to reduce total harmonic distortion and the effect of temperatur

Design and practice of simple first-order all-pass filters using commercially available IC and their applications

First-order all-pass filter circuits, both non-inverting and inverting, could be the focus of this article, which could include the design and implementation of first-order all-pass filter circuits. Using a standard integrated circuit (IC): AD830, as well as a single resistor and a single capacitor, the proposed first-order all-pass filters could well be built. The AD830 is an integrated circuit (IC) manufactured by Analog Devices Corporation that is available for purchase. The pole frequency and phase response of the proposed all-pass filters could well be directly modified by attuning the resistor in the circuit. Aside from that, the output voltage has a low impedance, making it appropriate for use in voltage-mode circuits. In addition, the proposed first-order all-pass filter is used to design the multiphase sinusoidal oscillator, which serves as an example of an application wherein the oscillation condition can be adjusted without impacting the frequency. The gain and phase responses of the proposed all-pass filters, as well as their phase response adjustment, time-domain response, and total harmonic distortion of signals, are all shown via computer simulation using the PSPICE software, as well as their experimental results. For the proposed circuits, a statistical analysis is coupled with a Monte Carlo simulation to estimate the performance of the circuits. In accordance with the results of this study, a theoretical design suitable for developing a worksheet for teaching and learning in electrical and electronic engineering laboratories has already been develope

Reconfigurable of current-mode differentiator and integrator based-on current conveyor transconductance amplifiers

The reconfigurable of the differentiator and integrator based on current conveyor transconductance amplifiers (CCTAs) have been presented in this paper. The proposed configurations are provided with two CCTAs and grounded elements. The configurations can be operated in the differentiator and integrator by selecting external passive elements. The input and output currents have low and high impedances, respectively; therefore, the configurations can be cascaded without additional current buffer. The proposed configurations can be electronically tuned by external direct current (DC) bias currents, and it also has slight fluctuation with temperature. An application of universal filter is demonstrated to confirm the ability of the proposed configurations. The results of simulation with Pspice program are accordance with the theoretical analysis

Active-only current-mode first-order allpass filter and its application in quadrature oscillator

The current-mode first-order allpass filter (APF) using only the active elements has been studied in the present paper. The proposed circuit comprises two operational transconductance amplifiers (OTAs) and one operational amplifier (OA) which is suitable to future development into an integrated circuit. The pole frequency and phase response can be electronically adjusted with changing the dc bias currents of OTAs. The APF has high output impedance, which is easy to cascade in high-order filter or drive load without using a buffering device. The current-mode quadrature oscillator is included to show the usability of the proposed filter. The results of PSPICE simulation are accordant with the theoretical analysis

Active-only current-mode first-order allpass filter and its application in quadrature oscillator

557-563The current-mode first-order allpass filter (APF) using only the active elements has been studied in the present paper. The proposed circuit comprises two operational transconductance amplifiers (OTAs) and one operational amplifier (OA) which is suitable to future development into an integrated circuit. The pole frequency and phase response can be electronically adjusted with changing the dc bias currents of OTAs. The APF has high output impedance, which is easy to cascade in high-order filter or drive load without using a buffering device. The current-mode quadrature oscillator is included to show the usability of the proposed filter. The results of PSPICE simulation are accordant with the theoretical analysis. </span

Electronically Controlled Biquadratic Filter and Quadrature Oscillator Using CDTAs

This article presents a current-mode biquadratic filter and quadrature oscillator circuit based on current differencing transconductance amplifiers (CDTAs). The proposed circuit does not require changing the circuit topology. In addition to the low-pass filter, high-pass filter, band-pass filter, and sinusoidal quadrature signal, the proposed circuit has a pole frequency that can be controlled independently from the quality factor, while the oscillation frequency can be controlled non-interactively. The circuit impedance with high output can directly drive the load without using a current buffer. Furthermore, grounded capacitors can function without the use of external resistors. This qualification is ideal for the future development of integrated circuits (ICs). After the PSPICE simulation with 90 nm CMOS parameters and the experiments by commercial ICs, the results are consistent with the theoretical analysis of the proposed circuit

Current-mode MISO filter using CCCDTAs and grounded capacitors

This paper presents the current-mode multi-input single-output (MISO) biquadratic filter using current-controlled current differencing tranconductance amplifier (CCCDTA) as an active building block. The proposed circuit comprises three CCCDTAs and two grounded capacitors performing completely standard functions: low-pass, high-pass, band-pass, band-reject and all-pass functions and does not require double input current signals as well as inverting input currents. The pole frequency and quality factor of the proposed circuit can be adjusted electronically/independently via dc bias currents. In addition, the filter circuit has low-input and high-output impedance which facilitates easy connecting for current-mode circuit. The proposed circuit uses all grounded capacitors which is very suitable to further develop into an integrated circuit and without requiring any matching condition. Moreover, the active and passive sensitivities are low. The PSPICE simulation results are included to show the workability of the proposed circui

Current-mode MISO filter using CCCDTAs and grounded capacitors

470-477This paper presents the current-mode multi-input single-output (MISO) biquadratic filter using current-controlled current differencing tranconductance amplifier (CCCDTA) as an active building block. The proposed circuit comprises three CCCDTAs and two grounded capacitors performing completely standard functions: low-pass, high-pass, band-pass, band-reject and all-pass functions and does not require double input current signals as well as inverting input currents. The pole frequency and quality factor of the proposed circuit can be adjusted electronically/independently via dc bias currents. In addition, the filter circuit has low-input and high-output impedance which facilitates easy connecting for current-mode circuit. The proposed circuit uses all grounded capacitors which is very suitable to further develop into an integrated circuit and without requiring any matching condition.<span style="font-size:10.0pt; font-family:" times="" new="" roman","serif";mso-fareast-font-family:calibri;="" mso-bidi-font-family:mangal;mso-ansi-language:en-us;mso-fareast-language:en-us;="" mso-bidi-language:hi"=""> Moreover, the active and passive sensitivities are low. The PSPICE simulation results are included to show the workability of the proposed circuit.</span