KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 34

Some of the metrics are blocked by your
consent settings
Nano-Power OTA-Based Low-Pass Filter for Ultra-Low-Energy Biomedical Signal Processing
(2026-05-01)
Kulej, Tomasz
;
Kumngern, Montree
;
Khateb, Fabian
This paper presents a nanowatt-scale operational transconductance amplifier (OTA) and an electronically tunable third-order low-pass filter (LPF) designed for energy-constrained biomedical signal conditioning. The circuits are implemented in a 65 nm CMOS process and verified through comprehensive schematic-level simulations. Biased in the deep subthreshold region at 1 nA, the OTA achieves a 50 dB low-frequency gain, a 225 Hz unity-gain bandwidth at 10 pF load capacitance and an input-referred noise floor of 1.55 μV/√Hz, with a total power consumption of only 1.75 nW. The integrated third-order LPF provides a wide tuning range (37–668 Hz) via bias current modulation, exhibiting excellent linearity with a THD of 0.059% and a 65.3 dB dynamic range. Monte Carlo and PVT corner analyses demonstrate the design’s theoretical robustness against process variations and environmental fluctuations. ECG signal simulations validate the circuit’s effectiveness in suppressing high-frequency artifacts while preserving morphological integrity, providing a proof-of-concept for ultra-low-power wearable healthcare architectures.
Some of the metrics are blocked by your
consent settings
0.5 V, nW-Range Universal Filter Based on Multiple-Input Transconductor for Biosignals Processing
(2022-11-01)
Khateb, Fabian
;
Kumngern, Montree
;
Kulej, Tomasz
;
Akbari, Meysam
;
Stopjakova, Viera
This paper demonstrates the advantages of the multiple-input transconductor (MI-G<inf>m</inf>) in filter application, in terms of topology simplification, increasing filter functions, and minimizing the count of needed active blocks and their consumed power. Further, the filter enjoys high input impedance, uses three MI-G<inf>m</inf>s and two grounded capacitors, and it offers both inverting and non-inverting versions of low-pass (LPF), high-pass (HPF), band-pass (BPF), band-stop (BS) and all-pass (AP) functions. The filter operates under a supply voltage of 0.5 V and consumes 37 nW, hence it is suitable for extremely low-voltage low-power applications like biosignals processing. The circuit was designed in a Cadence environment using 180 nm CMOS technology from Taiwan Semiconductor Manufacturing Company (TSMC). The post-layout simulation results, including Monte Carlo and process, voltage, temperature (PVT) corners for the proposed filter correlate well with the theoretical results that confirm attractive features of the developed filter based on MI-G<inf>m</inf>.
Some of the metrics are blocked by your
consent settings
High-order chebyshev notch filter based on MO-OTA and its application in Biosensor
(2021-05-19)
Srisamranrungrueang, Siradanai
;
Wongprommoon, Natapong
;
Prommee, Pipat
This paper presents a high-order notch filter based on multiple output OTA (MO-OTA). The signal flow graph (SFG) method is applied as a design procedure based on the RLC prototype. The RLC Chebyshev low-pass filter is used as an original prototype. The network transform is applied to convert the LPF to a notch filter. From the SFG, the denormalized network can be replaced by integrators and differentiators. The current-mode lossy and lossless types of integrator and differentiator are realized by using CMOS MO-OTA and grounded capacitor. A simple and low-complexity structure is achieved and constructed by 9 MO-OTAs and 6 grounded capacitors. The stop-band frequency between 10Hz-1kHz can be electronically tuned by the bias current between 1-100 μA. The low power supply ±0.75V is required which consumes the power 15mW at 100μA bias current. An application in ECG signal with power line interference (PLI) removal is included.
Some of the metrics are blocked by your
consent settings
Tunable Elliptic High-pass Filter based on Differentiator Approach
(2020-09-23)
Wongprommoon, Natapong
;
Pienpichayapong, Peradol
;
Prommee, Pipat
This article presents a design of high-order Elliptic ladder high-pass filter based on differentiators and integrator approach. Since the design of general Elliptic high-pass filter can be realized with high complexity, moreover the high-pass filter held very complicated design. The differentiators and integrator are deployed for synthesis high-pass filter from its Signal Flow Graph (SFG). The Elliptic RLC high-pass filter is transformed by using the original Elliptic RLC low-pass filter. The SFG is straightforward analyzed from the Elliptic RLC high-pass filter prototype. The SFG describes three differentiators and one integrator. The operational transconductance amplifiers (OTA) and grounded capacitors are preferred to implement the differentiators and integrator. The proposed filter contains only 7 OTAs with 4 grounded capacitors. The frequency responses can be varied between 100kHz and 10MHz by manipulating the bias current (IB) from 1μA to 100μA. The performances and the capability are carried out by using PSpice simulation which agreed to the theory.
Some of the metrics are blocked by your
consent settings
Design of Electronically Controllable Quadrature Sinusoidal Oscillator with Linear Control of Frequency
(2019-12-01)
Jaikla, Winai
;
Suwanjan, Peerawut
;
Chaichana, Amornchai
;
Sotner, Roman
In this paper, the design of sinusoidal oscillator which generates two output voltages with 90° degree phase difference is presented. The design procedure is started from the function block diagram to proposed oscillator using commercially available ICs. The proposed oscillator is constructed from three OTAs, one voltage summing circuit, one grounded resistor and two grounded capacitors. The frequency of the generated sinusoidal waveform is electronically and linearly controlled without disturbing the condition for oscillating of the system. With this feature, the proposed oscillator is used to generates the frequency modulation (FM) signal. The magnitude of the quadrature voltage waveform is equal during adjusting the generated frequency. A Pspice simulation and experiment are done to verify the performance of the proposed circuit. The macro models of available ICs, LM13700 and AD830 are employed for simulation. The simulation and experimental results confirm theory well as expected.
Some of the metrics are blocked by your
consent settings
Electronically controlled voltage mode first order multifunction filter using low-voltage low-power bulk-driven OTAs
(2019-09-01)
Jaikla, W.
;
Talabthong, Pruedchawat
;
Siripongdee, Surapong
;
Supavarasuwat, Piya
;
Suwanjan, Peerawut
In this paper, a new versatile voltage mode first order filter using low-voltage low-power bulk-driven OTAs is presented. The proposed filter with two high impedance input-voltage nodes and single output-voltage node consists of two OTAs, one grounded capacitor and one grounded resistor. Three filtering responses, low-pass (LP), high-pass (HP) and all-pass (AP) are obtained by appropriately applying the input signal into the input nodes. The natural frequency (ω<inf>0</inf>) can be electronically tuned by the bias current. In case of all-pass filter, its phase response is electronically controlled by adjusting only single bias current. With this feature, it doesn't need to simultaneously change two bias currents or two passive element values. The performances of the proposed filter were evaluated via PSPICE simulations using CMOS 0.18 μm TSMC technology parameters (level 7) with ±0.4 V supply voltages. The proposed filter consumes 47.2 μW. To obtain the actual testing results, the proposed filter was also experimented using commercially available IC, LM13700. Moreover, the three phases sinusoidal oscillator based on proposed first order high-pass filter was designed and investigated by PSPICE simulation and experiment.
Some of the metrics are blocked by your
consent settings
Frequency tunability of fractance device based on OTA-C
(2019-07-01)
Prommee, Pipat
;
Wongprommoon, Natapong
;
Sotner, Roman
This paper presents the realization of fractance device by using an approximating function. From this function, we can obtain the characteristic of fractional passive element with constant phase at specific bandwidth. The approximating functions can be realized by RC network. Unfortunately, the RC passive network is not suitable for integration and lack of interesting features as well as frequency tuning. Hence, this paper proposes the realization of fractional device based on OTA-C without any resistor. The rational functions were simplified to series expansion that can realize by low-complexity OTA-C. Due to the biomedical applications, the device order of 0.507 and 0.766 are given in this paper. The results show the magnitudes and phases in agreement with the theory and also approximating functions. Frequency tunability feature is obtained from 100Hz to 10kHz by adjusting I<inf>B</inf> from 1μ A to 100 μ A. PSpice simulation results are carried out to confirm with the theory.
Some of the metrics are blocked by your
consent settings
OTA-C based compact Low-pass Elliptic Filter
(2018-12-24)
Wongprommoon, Natapong
;
Manositthichai, Narongsak
;
Prommee, Pipat
This article described a compact structure simulating electronically controlled high-order Elliptic filter based on OTA-C. The signal flow graph (SFG) is deployed as a synthesis method from RLC prototype. The synthesis of Elliptic filter using SFG is normally required the integrators and very low current/voltage gain. This proposed filter is synthesized by using SFG and no required any current/voltage gains. From its SFG, the OTA-C based integrators and differentiators can be realized. The completed circuit is using only grounded capacitors with low-complexity structure. The frequency response of proposed filter can be tuned through the equality of OTA's bias currents. The supply voltage is using ±. The comparison of proposed filter and RLC prototype characteristics are verified by PSpice that the results are in good agreement.
Some of the metrics are blocked by your
consent settings
Fully tunable all-pass filter using OTA and its application
(2016-11-28)
Saising, Ekkapong
;
Prommee, Pipat
This paper proposes a realization of fully tunable all-pass (AP) filter and its application. Three Multiple Outputs Operational Transconductance Amplifiers (MOOTAs) and a grounded capacitor are used for realizing an all-pass filter which is able to tune in both of the frequency response and gain. The frequency response and gain are independently tuned through particular bias current. The advantage of independent tunable gain is of AP filter that can be widely used in many applications as well as the sinusoidal oscillator. A multiphase sinusoidal oscillator (MSO) using loop-back of three cascaded all-pass sections is raised as an application. Three MOOTAs and a grounded capacitor are constructed as current-mode APN. The PSpice simulations results are described in two parts, AP filter and MSO. It shows the magnitude and phase responses can be independently tuned. The MSO current and voltage outputs are equally spaced in phase of 360/n degree. The harmonic distortion of the sinusoidal output is less than 0.64%.
Some of the metrics are blocked by your
consent settings
OTA high pass filter-based multiphase sinusoidal oscillator
(2015-10-09)
Thongdit, Preecha
;
Kunto, Terdsak
;
Prommee, Pipat
This paper proposes a new approach to implement a multiphase sinusoidal oscillator using loop-back of n-cascaded high-pass filters form. Two basic CMOS Multiple Outputs Operational Transconductance Amplifier (MOOTA) and grounded capacitors are constructed as a current-mode high-pass filter. Gain and frequency response of high-pass filter can be independently tuned through the particular bias current. It is, therefore, orthogonally of oscillation condition and frequency oscillation is obtained through bias currents of each OTA. Multiphase sinusoidal current output and voltage output can be obtained with equally space in phase of 360/n degree. Third-order high-pass filter has been raised to confirm the theoretical agreement. Low-harmonic distortion of achieved sinusoidal output less than 0.75% is obtained. The performances are carried out by PSpice for confirm its attractive characteristics.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results