18 research outputs found
New Electronically Tunable Third Order Filters and Dual Mode Sinusoidal Oscillator Using VDTAs and Grounded Capacitors
This study introduces a third order filter and a third order oscillator configuration. Both the circuits use two voltage difference transconductance amplifiers (VDTAs) and three grounded capacitors. By selecting the input and output terminals properly, current mode and transimpedance mode low-pass and band-pass filters can be obtained without component matching conditions. The natural frequency (Ï0) can be tuned electronically. The oscillator circuit provides voltage and current outputs explicitly. The condition of oscillation (CO) and the frequency of oscillation (FO) can be adjusted orthogonally and electronically. The workability of the configurations is judged using TSMC CMOS 0.18 ÎŒm technology parameter as well as commercially available LM13700 integrated circuits (ICs). The simulation results show that: for ±0.9V power supply, the power consumption is 1.08 mW for both the configurations, while total harmonic distortions (THDs) are less than 2.06% and 2.17% for the filter and oscillator configurations, respectively
Dual-mode multifunction filter realized with a single voltage differencing gain amplifier (VDGA)
This article presents the dual-mode multifunction biquad filter realized employing only a single voltage differencing gain amplifier (VDGA), one resistor and three capacitors. The proposed filterwith one input and three outputs can configure as voltage-mode or current-mode filter circuit with the appropriate input injection choice. It can also synthesis the three standard filter functions, which are highpass, bandpass, and lowpass responses without modifying the circuit configuration. Orthogonal adjustment between the natural angular frequency (o) and the quality factor (Q) of the filter is achieved. Detail analysis of non-ideal VDGA effects and circuit component sensitivity are included. The circuit principle is verified by means of simulation results with TSMC 0.35-m CMOS process parameters
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 â1800 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
Condition of phase angle for a new VDGA-based multiphase variable phase shift oscillator from 0o to 90o
A novel interesting type of variable phase angle voltage mode oscillator using modern building block has been presented in this paper. The new proposed oscillator configuration which uses four voltage differencing gain amplifier (VDGA) and two grounded capacitors can generate two sinusoidal signals that change out of phase by 0 to 90 degree. It has four floating and explicit voltage mode outputs where every two outputs have the same phase. The circuit is characterized by (i) the condition of phase angle of the oscillation (PO) (this concept is introduced for the first time in this paper) can be tuned electronically (ii) the gain of the floating outputs can be controlled independently (iii) it provides electronic control of condition of oscillation (CO) and independent control of frequency of oscillation (FO). The Total Harmonic Distortion (THD) of the output waveforms was obtained and the results were reasonability values (less than 4.5%). The non-ideal analysis and simulation results are investigated and confirmed the theoretical analysis based upon VDGAs implementable in 0.35ÎŒm CMOS technology. Simulation results include time response and frequency response outputs generated by using the PSPICE program
New Two Simple Sinusoidal Generators with Four 45o Phase Shifted Voltage Outputs Using Single FDCCII and Grounded Components
Two new 45o phase shifted sinusoidal oscillator configurations employing single Second Generation Fully Differential Current Conveyor (FDCCII), two grounded capacitors and two grounded resistors are presented. The proposed oscillators can provide four sinusoidal voltage outputs with each a 45o phase difference. These circuits can also be utilized as voltage-mode quadrature oscillators. Additional output stages incorporation in FDCCII can also result in current outputs spaced 45 degree apart. The proposed circuits enjoy the simplicity and less passive and active component. The Total Harmonic Distortion (THD) of the output waveforms was reasonability values (less than 4.5%). The circuits can supply two equi-quadrature outputs and the Lissajous patterns confirm the quadrature voltage output waveforms. The workability of the circuits is simulated by PSPICE 0.18 ÎŒm CMOS technology. The non-ideal analysis and simulation results verifying theoretical analyses are also investigated
Low Voltage Low Power Analogue Circuits Design
DisertaÄnĂ prĂĄce je zamÄĆena na vĂœzkum nejbÄĆŸnÄjĆĄĂch metod, kterĂ© se vyuĆŸĂvajĂ pĆi nĂĄvrhu analogovĂœch obvodĆŻ s vyuĆŸitĂ nĂzkonapÄĆ„ovĂœch (LV) a nĂzkopĆĂkonovĂœch (LP) struktur. Tyto LV LP obvody mohou bĂœt vytvoĆeny dĂky vyspÄlĂœm technologiĂm nebo takĂ© vyuĆŸitĂm pokroÄilĂœch technik nĂĄvrhu. DisertaÄnĂ prĂĄce se zabĂœvĂĄ prĂĄvÄ pokroÄilĂœmi technikami nĂĄvrhu, pĆedevĆĄĂm pak nekonvenÄnĂmi. Mezi tyto techniky patĆĂ vyuĆŸitĂ prvkĆŻ s ĆĂzenĂœm substrĂĄtem (bulk-driven - BD), s plovoucĂm hradlem (floating-gate - FG), s kvazi plovoucĂm hradlem (quasi-floating-gate - QFG), s ĆĂzenĂœm substrĂĄtem s plovoucĂm hradlem (bulk-driven floating-gate - BD-FG) a s ĆĂzenĂœm substrĂĄtem s kvazi plovoucĂm hradlem (quasi-floating-gate - BD-QFG). PrĂĄce je takĂ© orientovĂĄna na moĆŸnĂ© zpĆŻsoby implementace znĂĄmĂœch a modernĂch aktivnĂch prvkĆŻ pracujĂcĂch v napÄĆ„ovĂ©m, proudovĂ©m nebo mix-mĂłdu. Mezi tyto prvky lze zaÄlenit zesilovaÄe typu OTA (operational transconductance amplifier), CCII (second generation current conveyor), FB-CCII (fully-differential second generation current conveyor), FB-DDA (fully-balanced differential difference amplifier), VDTA (voltage differencing transconductance amplifier), CC-CDBA (current-controlled current differencing buffered amplifier) a CFOA (current feedback operational amplifier). Za ĂșÄelem potvrzenĂ funkÄnosti a chovĂĄnĂ vĂœĆĄe zmĂnÄnĂœch struktur a prvkĆŻ byly vytvoĆeny pĆĂklady aplikacĂ, kterĂ© simulujĂ usmÄrĆovacĂ a induktanÄnĂ vlastnosti diody, dĂĄle pak filtry dolnĂ propusti, pĂĄsmovĂ© propusti a takĂ© univerzĂĄlnĂ filtry. VĆĄechny aktivnĂ prvky a pĆĂklady aplikacĂ byly ovÄĆeny pomocĂ PSpice simulacĂ s vyuĆŸitĂm parametrĆŻ technologie 0,18 m TSMC CMOS. Pro ilustraci pĆesnĂ©ho a ĂșÄinnĂ©ho chovĂĄnĂ struktur je v disertaÄnĂ prĂĄci zahrnuto velkĂ© mnoĆŸstvĂ simulaÄnĂch vĂœsledkĆŻ.The dissertation thesis is aiming at examining the most common methods adopted by analog circuits' designers in order to achieve low voltage (LV) low power (LP) configurations. The capability of LV LP operation could be achieved either by developed technologies or by design techniques. The thesis is concentrating upon design techniques, especially the nonâconventional ones which are bulkâdriven (BD), floatingâgate (FG), quasiâfloatingâgate (QFG), bulkâdriven floatingâgate (BDâFG) and bulkâdriven quasiâfloatingâgate (BDâQFG) techniques. The thesis also looks at ways of implementing structures of wellâknown and modern active elements operating in voltageâ, currentâ, and mixedâmode such as operational transconductance amplifier (OTA), second generation current conveyor (CCII), fullyâdifferential second generation current conveyor (FBâCCII), fullyâbalanced differential difference amplifier (FBâDDA), voltage differencing transconductance amplifier (VDTA), currentâcontrolled current differencing buffered amplifier (CCâCDBA) and current feedback operational amplifier (CFOA). In order to confirm the functionality and behavior of these configurations and elements, they have been utilized in application examples such as diodeâless rectifier and inductance simulations, as well as lowâpass, bandâpass and universal filters. All active elements and application examples have been verified by PSpice simulator using the 0.18 m TSMC CMOS parameters. Sufficient numbers of simulated plots are included in this thesis to illustrate the precise and strong behavior of structures.
A new wideband electronically tunable grounded resistor employing only three MOS transistors
In this paper, a new wideband electronically tunable grounded resistor, namely a grounded voltage controlled resistor (GVCR) including only three MOS transistors, is suggested. The proposed GVCR, without requiring any additional bias currents and voltages, has only one control voltage. Linearity analysis for the proposed GVCR is given. A new second-order multifunctional filter using two differential voltage current conveyors is also included as an application example. Some postlayout simulation results with SPICE are included to show the performance, workability, and effectiveness. © 2016 TĂŒbitak