Three-input Single-output Research Articles

Synthesis of electronically tunable multifunction biquad filter using voltage differencing differential input buffered amplifiers

AbstractBiquad filters are commonly used in analog circuits for various purposes in signal processing and communication applications. We synthesize an analog active biquad filter with five types of voltage‐mode filtering functions. The filter is synthesized using a parallel passive resistor‐inductor‐capacitor (RLC) network and unity‐gain voltage differencing amplifier. A voltage differencing differential input buffered amplifier (VD‐DIBA) is the main active component, and the biquad filter has a three‐input single‐output (TISO) topology. By replacing the passive inductor and resistor with VD‐DIBA‐based inductance and resistance simulators with a subtractor, the TISO voltage‐mode versatile filter is obtained from two VD‐DIBAs, one resistor, and two capacitors connected to the ground. The proposed filter can provide five types of voltage‐mode filtering functions: inverting bandpass and lowpass responses as well as noninverting band‐stop, high‐pass, and all‐pass responses. The all‐pass filter requires no additional active components. The three input voltage nodes have high impedance, and a low‐impedance output voltage node facilitates cascade connections without using additional voltage buffers. In addition, the natural frequency and quality factor can be electronically tuned. The quality factor is controlled without disturbing the passband gain and natural frequency. The proposed filter is simulated and verified experimentally in the Personal Simulation Program with Integrated Circuit Emphasis (PSPICE) and through laboratory tests employing VD‐DIBAs implemented using commercially available components.

Dual-Mode Single-Input Three-Output Multifunction Filter and Quadrature Oscillator Consisting of Two Voltage Differencing Transconductance Amplifiers and Two Grounded Capacitors

Dual-Mode Single-Input Three-Output Multifunction Filter and Quadrature Oscillator Consisting of Two Voltage Differencing Transconductance Amplifiers and Two Grounded Capacitors

High-performance single-input three-output DC–DC high gain converter for fuel cell-based electric vehicles

The electric vehicle (EV) requirement has various glitches and solutions in EV technology. Alternate energy that delivers the required power to the EVs is derived from the fuel cell with high performance. Nevertheless, the output voltage obtained from the fuel cell system is very less, and it is not enough to drive the motor of the EVs. The DC–DC converter increases the output voltage of the fuel cell system, and the EV also requires a different output voltage for the entire system. The DC–DC converter for fuel cell-based EVs requires high voltage gain with high conversion efficiency. However, the converter based on single-input three-output (SITO) DC–DC unidirectional converter can reduce loss and the cost of the system, and hence the overall efficiency. In this paper, a new single power-switch-based SITO converter topology is proposed to improve the voltage gain and conversion efficiency. The converter presented in this paper acts as a front-end DC–DC converter for the DC–AC inverter, and it supplies power to the auxiliary DC loads or for charging the auxiliary battery in EV. The converter has a single-stage voltage multiplier cell with a voltage clamp circuit to improve the voltage gain with soft-switching to reduce the loss, and hence the efficiency. The proposed converter is operated with a single MOSFET switch which delivers three different output levels with less voltage stress across the switch is the main feature of the proposed converter. The theoretical analysis is validated through the experimental results, and results verify that the proposed converter is best suitable for EV applications.

Second Order Universal Filter Using Four Terminal Floating Nullor (FTFN)

In this research paper, a voltage mode second order universal filter using Four Terminal Floating Nullor (FTFN) is presented. The proposed design uses Three Input Single Output (TISO) for the realization of all filter responses namely Low Pass Filter (LPF), High Pass Filter (HPF), Band Pass Filter (BPF), Notch Filter (NF) and All Pass Filter (APF) by using proper input selection. The analog building block, FTFN is simply realized with two commercially available AD844 ICs. The proposed second order universal filter comes with a single FTFN block with four passive components in which no component matching is required for filter realization. The universal filter is well verified using PSPICE simulation. In addition, experimental verification for the second order APF has been performed that confirms the theoretical expectations.

A New Nonisolated Single-Input Three-Output High Voltage Gain Converter With Low Voltage Stresses on Switches and Diodes

In this paper, an expandable single-input three-output high step-up dc–dc boost converter is proposed. The voltage conversion ratio of the output ports of the converter can be increased by inductor-diode-capacitor and diode-capacitor cells. The proposed converter can be applied in renewable energy conversion systems, such as in photovoltaic and fuel cells. Also, due to the three output ports of the converter, it can be utilized in portable devices which require high voltage conversions. The main advantage of the proposed converter is supplying loads with different voltages and current ranges due to the expandable structure of the converter. Besides, the proposed converter has the merit of achieving high voltage gains at high frequencies without preselecting wide duty cycles. Furthermore, the proposed converter is able to achieve higher voltage ranges without having any transformer or coupled inductors in its structure; consequently, the related drawbacks are avoided. The switching pattern of the converter is simple and both switches are on and off simultaneously. In this study, a single switching period of the proposed converter, the voltage conversion ratios of the output ports and the expanded form of the structure are analyzed theoretically. Finally, to verify the theoretical results, the experimental results for 40-V input/200-V, 100-V and 360-V outputs with total 600-W output power are extracted and compared with each other.

Actively Tunable Terahertz Switches Based on Subwavelength Graphene Waveguide.

As a new field of optical communication technology, on-chip graphene devices are of great interest due to their active tunability and subwavelength scale. In this paper, we systematically investigate optical switches at frequency of 30 THz, including Y-branch (1 × 2), X-branch (2 × 2), single-input three-output (1 × 3), two-input three-output (2 × 3), and two-input four-output (2 × 4) switches. In these devices, a graphene monolayer is stacked on the top of a PMMA (poly methyl methacrylate methacrylic acid) dielectric layer. The optical response of graphene can be electrically manipulated; therefore, the state of each channel can be switched ON and OFF. Numerical simulations demonstrate that the transmission direction can be well manipulated in these devices. In addition, the proposed devices possess advantages of appropriate ON/OFF ratios, indicating the good performance of graphene in terahertz switching. These devices provide a new route toward terahertz optical switching.

Universal Biquadratic filter with minimum number of Active FTFN

A new three input single output (TISO) biquad filter based on a four terminal floating nullor (FTFN) is presented. The proposed universal filter uses a single FTFN with four passive components which realizes all frequency responses namely, low pass filter (LPF), high pass filter (HPF), band pass filter (BPF), all pass filter (APF) and notch filter (NF) respectively. The proposed structure does not require any component matching and is free from non-ideal behavior. The sensitivity of the proposed filter parameters is found to be less than unity. PSPICE program simulations using commercially available IC AD844 are given to validate the performance of the filter and verify the theory.

Current mode filters with reduced complexity using a single EX-CCCII

In this paper an active element Extra-X current controlled conveyor (EX-CCCII) is used to reduce the complexity of some existing circuits. Two second-order current-mode biquadratic filter circuits are proposed, each using a single active element and two grounded capacitors. The first circuit is three input single output (TISO) and the second one is single input three outputs (SITO) biquadratic filter. The First circuit can realize all the standard filter transfer functions, while the second circuit can realize LP, BP and HP responses. The study of non-idealities and parasitics of the active element and their effects on transfer functions is carried out. The new circuits are found to be simpler than the earlier ones in terms of number of transistors. The functionality of the proposed biquadratic filters is verified through detailed PSPICE simulations using 0.25µm TSMC CMOS technology parameters.

Three-Input Single-Output Voltage-Mode Multifunction Filter with Electronic Controllability Based on Single Commercially Available IC

This paper presents a second-order voltage-mode filter with three inputs and single-output voltage using single commercially available IC, one resistor, and two capacitors. The used commercially available IC, called LT1228, is manufactured by Linear Technology Corporation. The proposed filter is based on parallel RLC circuit. The filter provides five output filter responses, namely, band-pass (BP), band-reject (BR), low-pass (LP), high-pass (HP), and all-pass (AP) functions. The selection of each filter response can be done without the requirement of active and passive component matching condition. Furthermore, the natural frequency and quality factor are electronically controlled. Besides, the nonideal case is also investigated. The output voltage node exhibits low impedance. The experimental results can validate the theoretical analyses.

OTA기반의 차단대역 조정이 가능한 3-입력/1-출력 구조의 다기능 Gm-C 필터

A new electronically stopband tunable filter is proposed with three-input single-output using Operational Transconductance Amplifier (OTA) in this paper. The proposed filter provides band pass, low pass and high pass multifunctional responses. Centre frequency () and quality factor (Q) of the realized filters could independently tuned without disturbing each other. Various network sensitivity and non-ideal characteristic analysis are done to check the sensitivity and parasitic effect of different circuit parameters. The CMOS realization of filter is done with 1.8V-0.18um process parameters and HSPICE simulation results are presented to assert the presented theory.

A low power current controllable single-input three-output current-mode filter using MOS transistors only

A novel circuit configuration for the realization of low power single-input three-output (SITO) current mode (CM) filters employing only MOS transistors are presented. The proposed circuit can realize low-pass (LP), band-pass (BP) and high-pass (HP) filter functions simultaneously at three high impedance outputs without changing configuration. Despite the other previously reported works, the proposed circuit is free from resistors and passive capacitors. Instead of passive capacitors; the gate-source capacitor of MOS transistor is used making the proposed circuit ideally suitable for integration. Compared to other works, the proposed filter has also the lowest number of transistors and lowest power consumption. The proposed circuit exhibits low-input and high-output impedances, which is highly desirable for cascading in CM signal processing. Moreover, it is center frequency can be electronically adjusted using a control current without a significant effect on quality factor (Q) granting it the highly desirable capability of electronic tunability. Transfer functions of the LP, BP and HP outputs are derived and the performance of the proposed circuit is proved through pre layout and post layout simulations at supply voltage of 1.8V and using 0.18μm CMOS process parameters. The power consumption and the required chip area are only 0.5mW and 77.4μm×70.2μm, respectively.

Compact VDTA-based current-mode electronically tunable universal filters using grounded capacitors

This paper presents a compact current-mode three-input single-output (TISO) type universal filter. Only one voltage differencing transconductance amplifier (VDTA) and two grounded capacitors are employed in the proposed filter. The circuit can realize lowpass, bandpass, highpass, bandstop and allpass biquadratic filter outputs by connecting the appropriate inputs, and offers electronic control of the natural angular frequency (ω0) and quality factor (Q) by means of adjusting the transconductance gain of the VDTA. In addition, by slight modification of the proposed scheme, another more useful TISO construction with orthogonal ω0–Q tuning has been obtained. Both the discussed universal filters have been shown to have low incremental active and passive sensitivities. To demonstrate the performances of the filters and verify the theoretical analysis, computer simulations are accomplished with the PSPICE program.

Current and voltage transfer function filters using a single active device

In this study, current and voltage transfer function filters using single active component, namely, current backward transconductance amplifier (CBTA) are presented. The proposed structures are a single-input three outputs (SITO) current-transfer function filter, a single-input four-output (SIFO) voltage transfer function filter and three-input single-output (TISO) voltage transfer function filter. The proposed filters have low active and passive sensitivities and use canonical number of electronics components. The validity of the proposed circuits is demonstrated by PSPICE simulations and experimental results. Operation range of the CBTA and its parasitic effects are also discussed.

All-Grounded Passive Elements Voltage-Mode DVCC-Based Universal Filters

In this paper two new voltage-mode (VM) universal filters employing three plus-type differential voltage current conveyors (DVCC+s) and grounded passive elements are presented. The first proposed filter is a single-input five-output (SIFO) circuit which can realize simultaneously all of the standard responses, i.e. low-pass (LP), band-pass (BP), high-pass (HP), all-pass (AP) and notch (NH) from the same configuration. The second proposed circuit is a three-input single-output (TISO) universal filter for realizing standard responses depending on the selection of the input signal from the same topology. Both of the proposed filters have the advantage of a high input impedance, which enables easy cascading to obtain higher order filters. The proposed filters are simulated using the SPICE program to verify the theoretical analysis.

Voltage-Mode Multifunction Filters Employing a Single DVCC and Grounded Capacitors

In this paper, two novel voltage-mode (VM) single-input-three-output (SITO) second-order multifunction analog filters for simultaneously realizing low-pass, bandpass, and high-pass responses from the same topology are proposed. They employ a single dual-output differential voltage current conveyor (DVCC), two grounded capacitors, and three resistors. Both of the proposed filters offer the following two important features: the simultaneous realization of low-pass, bandpass, and high-pass responses and the use of a minimum number of grounded capacitors and a single DVCC. The nonideal gain effects of the developed structures are examined. To show the performance of the proposed VM filters, computer simulation results using the SPICE program, together with ideal ones, are drawn.

Versatile universal electronically tunable current-mode filter using CCCIIs

A new versatile universal electronically tunable current-mode filter with three inputs and three outputs using three multiple-output current-controlled conveyors (MO-CCCIIs) and two grounded capacitors is proposed. The proposed configuration can be used as either a single-input three-output or three-input single-output. It can simultaneously realize all five different generic filtering signals: lowpass, bandpass, highpass, bandreject and allpass, unlike the previously reported works. It still maintains the following advantages: (i) the employment two grounded capacitors ideal for integrated circuit implementation, (ii) high output impedance good for cascadability for the current-mode circuits, (iii) no need to impose component choice, (iv) no need to employ inverting-type current input signals, and(v) low active and passive sensitivity performances. H-Spice and MATLAB simulations results are provided to demonstrate the theoretical analysis.

A Modified CFOA and Its Applications to Simulated Inductors, Capacitance Multipliers, and Analog Filters

In this paper, using a minimum number of passive components, i.e., new grounded and floating inductance simulators, grounded capacitance multipliers, and frequency-dependent negative resistors (FDNRs) based on one/two modified current-feedback operational amplifiers (MCFOAs), are proposed. The type of the simulators depends on the passive element selection used in the structure of the circuit without requiring critical active and passive component-matching conditions and/or cancellation constraints. In order to show the flexibility of the proposed MCFOA, a single-input three-output (SITO) voltage-mode (VM) filter, two three-input single-output (TISO) VM filters, and an SITO current-mode (CM) filter employing a single MCFOA are reported. The layout of the proposed MCFOA is also given. A number of simulations using the SPICE program and some experimental tests are performed to exhibit the performance of the introduced structures.

Voltage-mode FDCCII-based universal filters

Three new voltage-mode universal biquadratic filters configuration are proposed. The first proposed high-input impedance universal filter with single input and five outputs, which can simultaneously realize voltage-mode lowpass (LP), bandpass (BP), highpass (HP), bandstop (BS) and allpass (AP) filter responses employing all grounded passive components. The second proposed high-input impedance universal filter with three input and single output, which also can realize all the standard filter functions without requiring any inverting input voltage signal. The third proposed universal filter with three inputs and five outputs, which can be used as either a three-input single-output or a two-input five-output universal filter. Moreover, each of the proposed circuits still enjoys (i) the employment of only grounded capacitors, and (ii) no requirement with the component choice conditions to realize specific filtering functions.

Electronically Tunable Current-Mode Universal Filter Employing Only Plus-Type Current-Controlled Conveyors and Grounded Capacitors

A new current-mode current-controlled three-input single-output universal filter, which employs only five plus-type second-generation current-controlled current conveyors (CCCIIs) and two grounded capacitors, is presented in this paper. The proposed configuration provides lowpass, bandpass, highpass, bandstop, and allpass current responses at a high impedance terminal, which enables easy cascadability of the circuit. The filter also offers independent electronic control of the natural frequency ωo and the quality factor Q through adjusting of the bias current of the CCCII. Derived analytical expressions for the filter parameter deviations due to CCCII nonidealities are also included. PSPICE simulation results are performed to confirm the theoretical analysis.

Low input impedance trans-impedance type multifunction filter using only active elements

In this paper, a new trans-impedance mode single-input–three-output (SITO) filter using opamp compensation poles is presented. The proposed circuit is composed of two internally compensated operational amplifiers (OAs) and four single-output operational transconductance amplifiers (OTAs), without using any external passive elements. The proposed multifunction filter can realize lowpass, bandpass and highpass responses simultaneously all at low output impedances. No matching condition is required. The circuit is suitable for monolithic implementation either with complementary metal oxide semiconductor (CMOS) or bipolar technologies. All of active sensitivities are low. The performance of the circuit is tested using SPICE simulation program.