Prommee, Pipat
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Preferred name
Prommee, Pipat
Alternative Name
Prommee, P.
Main Affiliation
Email
pipat.pr@kmitl.ac.th
19 results
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Item type:Publication, Simple structure OTA-C elliptic band-pass filter(2019-07-01); ;Wongprommoon, Natapong ;Khateb, FabianManositthichai, NarongsakThis paper presents a new Elliptic ladder bandpass (BP) filter based on MO-OTA. This RLC ladder low-pass (LP) prototype and network transformation are used to create the band-pass signal flow graph (SFG). From SFG, the integrators and differentiator are required to realize the BP Elliptic filter with low-complexity configuration. The integrator and differentiator circuits can generally be obtained based on OTA-C technique. Lossy and lossless integrators and differentiators based on MO-OTA(s) are straight-forward applied to SFG for achieving the designed filter. Based on this technique, the circuit is obviously apparent that the final circuit has low-complexity and low-component count compared with the conventional technique. This proposed BP Elliptic filter contains only 10 bipolar MO-OTAs and 8 grounded capacitors. The frequency responses can be tuned between 2kHz and 100kHz through the bias currents of OTA. The simulation results are carried out by PSpice and agreed well with theory anticipation. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, OTA-based tunable fractional-order devices for biomedical engineering(2021-01-01); ;Pienpichayapong, Peradol ;Manositthichai, NarongsakWongprommoon, NatapongThis research realizes fractional-order devices or constant phase element (CPE) using continued fraction expansion (CFE) and rational function approximation methods. An RC ladder network prototype was realized using CFE based on the Cauer network principle. The RC ladder network and signal flow graph (SFG) were employed to realize the proposed CPE. Voltage gain circuits and voltage-mode integrators were realized by using operational transconductance amplifiers (OTA) and grounded capacitors. The proposed CPE was subsequently synthesized using voltage gain circuits and voltage-mode integrators based on SFG. The proposed CPE could function as fractional-order capacitor and fractional-order inductor. Besides, the CPE could be constructed in arbitrary fractional-orders. The impedance and operation frequency are independently tunable by manipulating OTA bias current. To validate, the proposed fractional-order device was applied to six types of electrical Cole models of skull tissues, and simulation results were compared with the approximation function and theory. The electrical characteristics of the Cole models based on the proposed CPE are comparable to the theoretical characteristics of the Cole model. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, High-order bp filter using biquad log-domain method(2018-07-02) ;Wongprommoon, Natapong ;Manositthichai, NarongsakHigh-order band-pass ladder filter based on Log-domain biquad functions is presented in this paper. High-order ladder filter is designed from RLC ladder filter prototype based on two types of biquad log-domain filters. Log-domain lossy and lossless integrator concepts are used to realize biquad log-domain filter in each type. Log-domain lossy integrator is easily realized by using 7 transistors and 1 grounded capacitor and log-domain lossless integrator is also easily realized by using log-domain lossy integrator by adding feedback to the input which consists of 8 transistors and 1 grounded capacitor. By adjusting bias current the frequency responses the filter can be obtain between 100 kHz and 100 MHz. This filter operates in transistor level which is suitable for operating in high frequency operation. A commercial array BJT technology is used in PSpice simulation. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Log-domain all-pass filter-based multiphase sinusoidal oscillators(2013-04-01); Wongprommoon, NatapongLog-domain current-mode multiphase sinusoidal oscillators based on all-pass filters are presented in this paper. The first-order differential equation is used for obtaining inverting and non-inverting all-pass filters. The proposed oscillators are realized by all-pass filters whose natural frequency and stage gain can be electronically tuned by adjusting the bias currents. Each all pass filter contains 10 NPN transistors and a grounded capacitor. The validated BJT model which is used in SPICE simulation operated by a single power supply as low as 2.5 V. The frequency of oscillation can be controlled over four decades. The total harmonic distortions of these MSO at frequency 56.67 MHz and 54.44 MHz, obtained around 0.52% and 0.75%, respectively. The proposed circuits enable fully integrated in telecommunication systems and also suit to high-frequency applications. Nonideality studies and PSpice simulation results are included to confirm the theory. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Integrable QPSK Modulator Using CMOS Technology(2018-08-20) ;Wongprommoon, Natapong ;Manositthichai, NarongsakThis paper presents a design of voltage-mode QPSK modulator circuit based on CMOS analog signal processing subsystems. The circuit consists of dual-output all-pass filter, analog switches and summing operator. All-pass filter is used as a phase-shifter which provides ± 90 degrees phase shifted at considered frequency. Trigonometric relationship identities are used for obtaining the completed 4-quadrant phase shifted signals. CMOS analog switches are constructed with the summing junction for obtaining the QPSK modulation signal outputs by arithmetic algorithm. All-pass filter and summing junction are realized by using CMOS-based differential voltage buffer (DVB) with a few passive elements. The results are verified by PSpice using ± 1.5V power supplies which are in agreement with the theory expectations. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Low-complexity Chebyshev High-pass Filter based on OTA-C(2020-07-01) ;Wongprommoon, Natapong ;Tiamsuphat, ApinatThis work presents a new Chebyshev ladder high-pass filter based on operational transconductance amplifier (OTA) based differentiators. Lossy and Lossless differentiators based on the OTA-C technique are deployed as the main sub-circuits. The Chebyshev ladder high-pass filter is transformed from a low-pass RLC prototype by using the network transformation method. The signal flow graph (SFG) and third-order RLC prototype are used to synthesis the active high-pass filter. The final SFG functions can be directly replaced by OTA-C current-mode differentiators. Due to the proposed structure of the high-pass filter contains only 6 OTA(s) and 3 grounded capacitors that resulting in the low-complexity and low components count. The frequency responses of the proposed filter can be electronically tuned between 200kHz and 8MHz by varying the bias currents (IB) from 3 μ A to 300 μ A. The proposed filter response good agreement with the response of the RLC prototype. PSpice simulation results are carried out to verify the filter performances. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Low-Cost Capacitive Sensor Front-End Circuit Based on Phase-Locked Technique(2025-12-15) ;Wongprommoon, Natapong ;Chimnoy, JiratThis research presents an efficient front-end circuit for grounded capacitive sensors (GCSs), based on a phase-locked technique. An all-pass filter serves as a phase shifter to obtain the desired 90° phase difference, enabling the sensor capacitance to be calculated from the locked frequency regardless of parasitic capacitances. For long-distance capacitance measurements (remote sensors), the proposed circuit integrates an improved active shield technique, allowing real-time measurements using only a low-cost microcontroller unit (MCU), display, and commercially available electronic components, without the need for expensive or bulky instruments. The design is fully automated and does not require manual adjustments. Simulation and experimental results are consistent and validate the effectiveness of the proposed method. Comparative experiments with standard instruments demonstrate accurate measurement within the 1–500 pF range through shielded cables up to 10 m, while maintaining a maximum nonlinear error (NLE) of only 0.04% full-scale span (FSS). The proposed circuit architecture effectively mitigates the effects of parasitic cable capacitance and the input capacitance of operational amplifiers. This approach provides a low-cost, compact, fast, and highly accurate solution, making it suitable for applications of liquid-level measurement in hazardous or hard-to-access environments through remote capacitive sensor measurement. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, OTA-C based compact Low-pass Elliptic Filter(2018-12-24) ;Wongprommoon, Natapong ;Manositthichai, NarongsakThis 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 yourconsent settings
Item type:Publication, High-order chebyshev notch filter based on MO-OTA and its application in Biosensor(2021-05-19) ;Srisamranrungrueang, Siradanai ;Wongprommoon, NatapongThis 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 yourconsent settings
Item type:Publication, OTA-based electronically tunable elliptic high-order current-mode ladder band-pass filter(2014-01-27) ;Wongprommoon, NatapongThis paper presents Elliptic high-order currentmode ladder band-pass filter based on OTA-C that can be operated in high frequency. High-order band pass filter is designed based on Elliptic Ladder band-pass filter prototype. The proposed filter contains lossy and lossless integrators. The frequency responses of band-pass filter can be electronically tuned between around 100kHz and 10MHz by adjusting bias current form 0.15 μA to 1500 μA with 7.74mW of dynamic power consumption along tuning the bias current. The circuit used 1.5 V power supply and used of ground capacitors which suit to integrated circuit. THD of band-pass filter can be obtained less than 1% along the operating frequencies. PSPICE simulation results are carried out to confirm the theory by using TSMC 0.18μm CMOS technology.
