Voltage-mode electronically tunable all-pass filter employing CCCII+, One capacitor and differential-input voltage buffer

This study aims to design an electronically tunable voltage-mode (VM) universal filter utilizing commercially available LT1228 integrated circuits (ICs) with three-input and single-output (TISO) configuration. With the procedure based on two integrator loop filtering structures, the proposed filter consists of two LT1228s, four resistors, and two grounded capacitors. It realizes five filter output responses: low-pass, all-pass, band-reject, band-pass, and high-pass functions. By selecting input voltage signals, each output responses can be achieved without changing the circuit architecture. The natural angular frequency can be controlled electronically. The input voltage nodes Vin1 and Vin3 possess high impedance. The output node has low impedance, so it can be cascaded to other circuits. The performance of the proposed filter is corroborated by PSpice simulation and hardware implementation which support the theoretical assumptions. The result shows that the range of total harmonic distortion (THD) is lower than 1%, and that the higher the temperature is, the lower the natural angular frequency is.

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Electronically Tunable Voltage-Mode All-Pass Filter Using Simple CMOS OTAs

2008 International Symposium on Communications and Information Technologies ◽

10.1109/iscit.2008.4700250 ◽

2008 ◽

Cited By ~ 4

Author(s):

Montree Kumngern ◽

Jirasak Chanwutitum ◽

Kobchai Dejhan

Keyword(s):

Pass Filter ◽

Voltage Mode ◽

Electronically Tunable

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

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v12i2.pp1308-1323 ◽

2022 ◽

Vol 12 (2) ◽

pp. 1308

Author(s):

Danupat Duangmalai ◽

Peerawut Suwanjan

Keyword(s):

Integrated Circuit ◽

Universal Filter ◽

Differential Input ◽

First Order ◽

Voltage Mode ◽

Transconductance Amplifier ◽

Low Pass ◽

Simulation And Experiment ◽

Electronically Tunable ◽

High Pass

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 (𝜔0) 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 𝑉. Verification of the theoretically described performances of the introduced electronically tunable universal filter was proved by the PSpice simulation and experiment.

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Versatile Tunable Voltage-Mode Biquadratic Filter and Its Application in Quadrature Oscillator

Sensors ◽

10.3390/s19102349 ◽

2019 ◽

Vol 19 (10) ◽

pp. 2349 ◽

Cited By ~ 4

Author(s):

San-Fu Wang ◽

Hua-Pin Chen ◽

Yitsen Ku ◽

Yi-Chun Lin

Keyword(s):

Input Voltage ◽

Angular Frequency ◽

Quadrature Oscillator ◽

Voltage Mode ◽

Single Output ◽

Tuning Characteristic ◽

Electronic Tuning ◽

Biquadratic Filter ◽

Single Input ◽

Electronically Tunable

This paper presents a versatile tunable voltage-mode biquadratic filter with five inputs and three outputs. The proposed filter enjoys five single-ended output operational transconductance amplifiers (OTAs) and two grounded capacitors. The filter can be easily transformed into a quadrature oscillator. The filter with grounded capacitors is resistorless and electronically tunable. Either a voltage-mode five-input single-output biquadratic filter or a voltage-mode single-input three-output biquadratic filter can be operated by appropriate selecting input and output terminals. In the operation of five-input single-output biquadratic filter, the non-inverting lowpass, non-inverting bandpass, inverting bandpass, inverting highpass, non-inverting bandreject, inverting bandreject, and non-inverting allpass filtering responses can be realized by appropriately applying the input voltage signals. In the operation of single-input three-output biquadratic filter, the non-inverting/inverting lowpass, bandpass and bandreject filtering responses can be realized simultaneously. The circuit provides independent adjustment of the resonance angular frequency and quality factor, high-input impedance, and no inverting-type input voltage signals are imposed. The application in quadrature oscillator exhibits independent electronic tuning characteristic of the oscillation condition and the oscillation frequency. The theoretical analysis has been verified through OrCAD PSpice and furthermore by experimental measurements.

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Design and Experiment of Electronically Tunable Voltage-Mode Biquad and Output Current Amplitude Oscillator

Applied Sciences ◽

10.3390/app11167357 ◽

2021 ◽

Vol 11 (16) ◽

pp. 7357

Author(s):

San-Fu Wang ◽

Hua-Pin Chen ◽

Yitsen Ku ◽

Fang-Yu Liu

Keyword(s):

Communication Systems ◽

Band Pass Filter ◽

Output Current ◽

Third Order ◽

Pass Filter ◽

Voltage Mode ◽

The Third ◽

Band Pass ◽

Electronically Tunable ◽

Electronically Controllable

This study presents an electronically tunable configuration for the design of a voltage-mode (VM) biquad with four input terminals and three output terminals. The proposed circuit employs four operational transconductance amplifiers (OTAs) and two grounded capacitors. Depending on the selections of the four input voltage signals, all the standard filtering functions can be realized. The proposed configuration simultaneously provides VM inverting band-pass, non-inverting low-pass, and non-inverting band-reject filtering functions without any component-matching choices. It offers the features of a resistorless structure, high-input impedance, electronic control of the pole frequency and quality factor, and low active and passive sensitivities. The measured power dissipation of the biquad is 0.96 W under 32 mA constant output current. The measured 1 dB power gain compression point of the output inverting band-pass filter is −7 dBm. The measured value of the third-order intercept point is 5.136 dBm, and the measured value of the third-order intermodulation distortion is −50.83 dBc. Moreover, the measured value of the spurious-free dynamic range is 53.49 dB, and the figure-of-merit of the biquad is 268.75 × 103. In addition, an electronically controllable quadrature oscillator (QO) with amplitude of output current can be realized using the proposed biquad. The proposed electronically controllable QO can provide an amplitude modulation signal or an amplitude shift keying signal, and is widely applied in signal processing systems and electronic communication systems. PSpice simulations and experimental results are accomplished.

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Electronically tunable voltage-mode Elliptic third-order ladder low-pass filter using simple OTA

2014 International Symposium on Intelligent Signal Processing and Communication Systems (ISPACS) ◽

10.1109/ispacs.2014.7024440 ◽

2014 ◽

Cited By ~ 1

Author(s):

Aphinat Tiamsuphat ◽

Pipat Prommee

Keyword(s):

Third Order ◽

Pass Filter ◽

Low Pass Filter ◽

Voltage Mode ◽

Low Pass ◽

Electronically Tunable

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Design of Voltage Mode Electronically Tunable First Order All Pass Filter in ±0.7 V 16 nm CNFET Technology

Electronics ◽

10.3390/electronics8010095 ◽

2019 ◽

Vol 8 (1) ◽

pp. 95 ◽

Cited By ~ 2

Author(s):

Muhammad Masud ◽

Abu A’ain ◽

Iqbal Khan ◽

Nasir Husin

Keyword(s):

Low Voltage ◽

Wide Frequency Range ◽

Passive Components ◽

Pass Filter ◽

First Order ◽

Voltage Mode ◽

Tunable Range ◽

Low Voltage Operation ◽

Unity Gain ◽

Electronically Tunable

A novel voltage mode first order active only tuneable all pass filter (AOTAPF) circuit configuration is presented. The AOTAPF has been designed using ±0.7 V, 16 nm carbon nanotube field effect transistor (CNFET) Technology. The circuit uses CNFET based varactor and unity gain inverting amplifier (UGIA). The presented AOTAPF is realized with three N-type CNFETs and without any external passive components. It is to be noted that the realized circuit uses only two CNFETs between its supply-rails and thus, suitable for low-voltage operation. The electronic tunability is achieved by varying the voltage controlled capacitance of the employed CNFET varactor. By altering the varactor tuning voltage, a wide tunable range of pole frequency between 34.2 GHz to 56.9 GHz is achieved. The proposed circuit does not need any matching constraint and is suitable for multi-GHz frequency applications. The presented AOTAPF performance is substantiated with HSPICE simulation program for 16 nm technology-node, using the well-known Stanford CNFET model. AOTAPF simulation results verify the theory for a wide frequency-range.

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