Kittipong Tripetch | Rajamangala University of Technology Suvarnabhumi (original) (raw)

Papers by Kittipong Tripetch

WSEAS Transactions on Circuits and Systems archive, 2019

An analysis of a BJT phase shift amplifier is proposed in a detail polynomial form. The numerator... more An analysis of a BJT phase shift amplifier is proposed in a detail polynomial form. The numerator and denominator polynomial form are derived which can be seen as a symbolic coefficient which are multiplied with complex frequencies of the order of the polynomial. A detail analysis is very laborious but it is presented some of the coefficients which are a function of the small signal parameters of the equivalent circuit such as a transconductance, output resistor, base spreading resistor, pi resistor, myu resistor and two parasitic capacitances, passive resistor for biasing, passive capacitors and resistors which are the core circuit of the phase shift networks. After dc operating point are designed as a function of the current consumption. All small signal parameters of the transistors of the phase shift amplifier are designed as a function of the current consumption. The BJT phase shift frequency response can be plotted by a polynomial form which can be calculated by MATLAB. The BJT phase shift amplifier may not worked as a phase shift oscillator without the input impedance formulas.

It is well known from communication system that ideal frequency modulator is the multiplication o... more It is well known from communication system that ideal frequency modulator is the multiplication of the carrier signal with information signal which can be model by cosine of the amplitude of sinusoidal of radio frequency signal. From this basic knowledge we can synthesize the circuit from this knowledge by using the exponential of the imaginary part of cosine of carrier signal plus or minus cosine of radio signal. By using bipolar junction transistor (low frequency or high frequency transistor). The collector current of the BJT can be solve as a function of the input carrier signal coupling with a capacitor or inductor and input radio frequency signal coupling with a capacitor or inductor so that the collector current can be a real part of the multiplication of both signal. After that, the collector current signal can be transformed by a 1 ohm resistor series with additional resistor so that it can be transformed into voltage at the anode of the additional diode or LED . The cathode of the diode or LED can be biased with resistive voltage divider. The output signal at the cathode of the diode can be cascade with operational amplifier to make an output. For the fully differential fm, the unknown supply voltage variable can be canceled with difference amplifier.

Two types of floating active resistors based on a complementary regulated cascode topology with c... more Two types of floating active resistors based on a complementary regulated cascode topology with cross-coupled regulated transistors are presented in this paper. The first topology is a high swing complementary regulated cascode active resistor. The second topology is a complementary common gate with a regulated cross coupled transistor. The small-signal input resistances of the floating resistors are derived. Three graphs of the input current versus the input voltage for different aspect ratios are designed and plotted using the Cadence Spectre 0.18-µm Rohm Semiconductor process. The total harmonic distortion graphs are plotted for three different aspect ratios with different input-voltage amplitudes and different input frequencies. From the simulation results, it is observed that a resistance of approximately 8.52 MΩ can be obtained from supply voltage at ±0.9 V.

This paper proposes for the first time symbolic formula of the power spectrum of CMOS Cross Coupl... more This paper proposes for the first time symbolic formula of the power spectrum of CMOS Cross Couple Oscillator and its modified circuit. Many principles existed to derived power spectrum in microwave textbook such as impedance, admittance parameters, ABCD, H parameters, etc. It can be compared by graph of power spectrum which methodology is the best from the point of view of practical measurement setup such as condition of impedance parameter which used superposition of current to derived (its current injection at the other port of the circuit is zero, which is impossible in reality). Four graphs of impedance parameters of cross couple oscillator are proposed. After that four graphs of scattering parameters of CMOS cross coupled oscillator will be shown.

2020 20th International Conference on Control, Automation and Systems (ICCAS), 2020

TENCON 2018 - 2018 IEEE Region 10 Conference, 2018

It is well known that a frequency multipliers used a diode for a frequency multiplication. The in... more It is well known that a frequency multipliers used a diode for a frequency multiplication. The infinite harmonic can be generated using diode with a sinusoidal input signal. The output of the frequency multiplier can be seen as a modulated wave if it is not a good result. This paper presented the high frequency multiplier by cascading a diode with a high order bandpass amplifier multiple times. An analysis and design are derived and simulated by MATLAB by using a SPICE model from Renesas Corp datasheet and a Schottky diode model from Hewlett Packard Corp.

World Academy of Science, Engineering and Technology, International Journal of Electronics and Communication Engineering, 2017

Introduction: Educational staff services play a role in determining the quality of education. Ser... more Introduction: Educational staff services play a role in determining the quality of education. Service quality is able to provide satisfaction for students. Students who were satisfied with the perceived quality will develop student loyalty to the institution. The purpose of this study was to assess the effect of educational staff service quality with the satisfaction and loyalty of nursing students so that the educational institutions as service providers are able to provide the best service and survive in the midst of competition. Method: The study was an explanative survey with a cross-sectional design. Data collection was conducted using both quantitative (questionnaires) and qualitative (Focus Group discussion/FGD) methods. This study used proportional random sampling, with 110 students as samples. The variables in this research were customer expectations, perceived quality, student satisfaction and loyalty. The data was collected by a questionnaire and analyzed by linear regression, while FGD was conducted in two different groups (students and staff's managers). Result: The result of the study explains the influence of student expectations on the perceived quality of the educational staff with a p-value = 0,002. There was no influence of student expectation on student satisfaction with a p-value = 0,156. The influence of the perceived quality of the educational staff towards student satisfaction had a p-value = 0,000. The influence of student satisfaction on student loyalty had a p-value = 0,000. Conclusion: The fulfilment of student expectations will have a positive impact on perceived quality. Furthermore, the positively perceived quality will create student satisfaction and student loyalty towards the educational institutions. For further research, it is suggested to examine the effect of satisfaction on student complaints.

Analog-digital mixed signal LSI plays an important role in the electronics. However, various on-c... more Analog-digital mixed signal LSI plays an important role in the electronics. However, various on-chip analog circuit designs have various tradeoffs and it is difficult to design. A filter and an oscillator are indispensable analog circuits. The active filter is important for a wide range of fields, such as a channel selection filter for wireless LAN, as a notch filter for 50 Hz, 60 Hz power interference cancellation, communication and biomedical signal acquisition. In addition, the oscillator is a core element for wireless communication and a clock for digital synchronous circuit. Based on this background, this research is conducting analog circuit design while comparing analytic and simulation method. Chapter 1 is an introduction, the background of this research and the Gm-C filter design previously proposed are summarized and the problems of the conventional design are summarized Chapter 2 discusses about noise analysis of Nauta’s transconductance amplifier. Usually, noise analysis must be derived by sum of mean square noise current source which is multiplied by square of output resistance divided by dc voltage gain. Equivalent output noise voltage of high order Gm-C filter simulation results are presented. Chapter 3 discusses about how to design two types of Gm-C filter called 5th order GmC elliptic filter and 10th order Gm-C elliptic filter based on element substitution which can be design from cutoff frequency, impedance scaling and filter table. The simulation results indicate that 5th-order elliptic Gm-C Low Pass Filter(LPF) shows the cut-off frequency dropped to 21.88 MHz due to high-frequency small-signal parasitic capacitances. The maximum input amplitude is -5.46 dBm for Total Harmonic Distortion(THD) less than 1%. The output noise is at -168dB at input frequency 1MHz. Chapter 4 discusses about Notch filter. This thesis proposed 2nd , 4th and 6th order Notch filter for interference rejection at 50 Hz which is the same frequency from high voltage power line. The architecture of 2nd order Notch filter from Kenneth Laker is chosen and designed. Magnitude response of 6th order Notch filter is simulated for 0.18 micron CMOS Process. The resistors in this block diagram can be substituted by floating active resistor if the notch filter is designed with very low cutoff frequency such as 50 Hz or 60 Hz, then, floating resistor is designed in the range of mega ohm which consumed very big layout area. For higher order notch filter, the theory is reviewed how to transform nth order of LPF LCR prototype into 2nth order of the notch filter LCR prototype. After the passive element value are computed from LCR prototype. Then, ground and floating active inductor can be designed from the value of the computed inductor value. Also, the biomedical signal acquisition LSI system is designed by modification of Twin-T 2nd order notch filter. Chapter 5 discusses about cross coupled oscillator design using Root Locus methodology. The time domain graph is shown as the result of four pole positions and four unknown constants which can be derived. The novel partial fraction expansion by multiplication of the factor denominator polynomial from the left side of the equation to the right side of the equation which is the conventional partial expansion instead of using the limit theorem. The fourth order polynomial can be factorized to have four pole frequencies. After that, the four unknowns can be computed by substituting the drain current into MATLAB file which are a function of the small signal parameters and passive element value such as capacitors, inductors and resistors. Usually, from simulation of the equations, the four unknowns are complex numbers. Thus, the solution of the four summation of term with each four unknowns has its own single poles can have four terms per unknowns because one unknown has real part and imaginary part and single pole can be exponential of complex number which can be expanded into real cosine plus or minus with imaginary sinusoidal function. It is found that from varying the time by using the period which is related with the oscillation frequency. The triangular wave waveform can be plotted as two graphs because underdamped real function has eight terms and underdamped imaginary function. Chapter 6 is a conclusion of the thesis.

The input impedance of a regulated cascode cross couple amplifier is derived. The frequency respo... more The input impedance of a regulated cascode cross couple amplifier is derived. The frequency response of the input impedance polynomial form can be plotted with MATLAB. From the polynomial form of the input impedance of the proposed circuit, it can be transformed by substitute complex frequency s with jω into the polynomial form equation. After that, this function can be grouped into a symbolic real and a symbolic imaginary form. The next step in derivation is to multiply this function with a complex conjugate function of the symbolic complex form of the input impedance. The last step is to plot a real and an imaginary part as a function of the input frequency so that the power amplifier can be matching with the various matching circuit according to the condition of the maximum power transfer.

International Journal of Circuits, Systems and Signal Processing, 2021

The polynomial form of the input impedance of a CMOS cross-coupled amplifier with NMOS only activ... more The polynomial form of the input impedance of a CMOS cross-coupled amplifier with NMOS only active inductor are proposed. The formula of polynomial form and novel coefficients are programmed in Scilab and MATLAB so that the pole position of the fourth order polynomial can be found. From experience of a simple cross coupled oscillator design, the proposed circuit diagram may not oscillate as a triangular wave signal because the two poles are complex (underdamped case) but its real part could not be minimized to 0.001 so that it has a stable amplitude and additional two poles are real poles. The impulse sensitivity function (ISF) of the proposed circuit is derived for the first time so that it may be used to derive phase noise in the future.

2019 Research, Invention, and Innovation Congress (RI2C), 2019

This paper presents microwave sensor system for moisture content measurement of paddy in hopper s... more This paper presents microwave sensor system for moisture content measurement of paddy in hopper silo. The sensor utilizes near-field transmission measurement technique operating at 400-500-MHz implemented by using double dipole antenna fabricated on FR-4 substrate. This proposed system is installed at the bottom of the hopper silo to collect moisture content. The moister contents of paddy in hopper silo from 12%–30% are measured and characterized. The extracted moisture contents from the sensors in this paper show an agreement of higher than 93% as compared with the commercial instrument in rice mill. In the system testing, the detection system is installed besides the silo 50 ton. IoT system was used to collect the result such as moisture and temperature of the system.

It is well known that input impedance of cross couple oscillator circuit has a fourth order denom... more It is well known that input impedance of cross couple oscillator circuit has a fourth order denominator polynomial form in frequency domain. Thus, it is important to design pole frequency by symbolic formula so that it is oscillate as a sinusoidal signal. It should be noted that in order for cross couple to oscillate, all pole frequency should be position on imaginary axis only in pole zero diagram. The graph of time domain response is plotted by using inverse Laplace's transform of the four unknowns of the partial fraction solution which were derived.

2015 Science and Information Conference (SAI), 2015

This paper proposed single stage CMOS complementary regulated cascode distributed amplifier (CRCD... more This paper proposed single stage CMOS complementary regulated cascode distributed amplifier (CRCDA) based on inductive coupling technique. Usually, distributed amplifier is based on inductive coupling between gate and gate terminal of MOSFET and between drain and drain terminal of MOSFET. But this paper proposes some new idea, by combining inductive coupling with circuit technique called CRCDA. There are three floating silicon inductors in the proposed circuit and twelve nodes of interconnection in the layout hierarchy.

2007 International Symposium on Intelligent Signal Processing and Communication Systems, 2007

ABSTRACT A fully differential rail-rail input stage and class AB output stage with and without co... more ABSTRACT A fully differential rail-rail input stage and class AB output stage with and without common-mode feedback circuit are proposed. There are at least 4 schematics to be proposed. The first schematic is CMOS rail-rail input stage and class AB output stage without common-mode feedback (CMFB) circuit. The second schematic is CMOS rail-rail input stage and class AB output stage with CMFB circuit. For low voltage operation, the tail current sources of the first and second schematics are removed. As a consequence, there is no voltage drop between drain and source terminals of the current source, and bulk-source voltage effect of the input transistor is removed.

The Fully differential operational amplifier (op-amp) schematics are compared in terms of specifi... more The Fully differential operational amplifier (op-amp) schematics are compared in terms of specifications such as unity gain frequency, current consumption. After choose LCR prototype, the proposed op-amp is used in 3rd order Butterworth response MOSFET-C lowpass filter. Simulation results using 0.35 um from TSMC corporation indicated that the proposed op-amp has an ability to have output signal swing from rail-rail (which means input output swings from positive to negative dc supply without distortion. MOSFET-C which used the proposed op-amp should have highest linearity if it is designed optimally. Figure of merit of fully differential op-amp is also proposed, this special specification of op-amp indicated that the proposed fully differential op-amp consumed least current at the same unity gain frequency compared with conventional schematics at least in simulation results. Experimental results from CMOS array of ALD1103, which is connected as fully differential op-amp, are used to ...

WSEAS Transactions on Circuits and Systems archive, 2019

An analysis of a BJT phase shift amplifier is proposed in a detail polynomial form. The numerator... more An analysis of a BJT phase shift amplifier is proposed in a detail polynomial form. The numerator and denominator polynomial form are derived which can be seen as a symbolic coefficient which are multiplied with complex frequencies of the order of the polynomial. A detail analysis is very laborious but it is presented some of the coefficients which are a function of the small signal parameters of the equivalent circuit such as a transconductance, output resistor, base spreading resistor, pi resistor, myu resistor and two parasitic capacitances, passive resistor for biasing, passive capacitors and resistors which are the core circuit of the phase shift networks. After dc operating point are designed as a function of the current consumption. All small signal parameters of the transistors of the phase shift amplifier are designed as a function of the current consumption. The BJT phase shift frequency response can be plotted by a polynomial form which can be calculated by MATLAB. The BJT phase shift amplifier may not worked as a phase shift oscillator without the input impedance formulas.

It is well known from communication system that ideal frequency modulator is the multiplication o... more It is well known from communication system that ideal frequency modulator is the multiplication of the carrier signal with information signal which can be model by cosine of the amplitude of sinusoidal of radio frequency signal. From this basic knowledge we can synthesize the circuit from this knowledge by using the exponential of the imaginary part of cosine of carrier signal plus or minus cosine of radio signal. By using bipolar junction transistor (low frequency or high frequency transistor). The collector current of the BJT can be solve as a function of the input carrier signal coupling with a capacitor or inductor and input radio frequency signal coupling with a capacitor or inductor so that the collector current can be a real part of the multiplication of both signal. After that, the collector current signal can be transformed by a 1 ohm resistor series with additional resistor so that it can be transformed into voltage at the anode of the additional diode or LED . The cathode of the diode or LED can be biased with resistive voltage divider. The output signal at the cathode of the diode can be cascade with operational amplifier to make an output. For the fully differential fm, the unknown supply voltage variable can be canceled with difference amplifier.

Two types of floating active resistors based on a complementary regulated cascode topology with c... more Two types of floating active resistors based on a complementary regulated cascode topology with cross-coupled regulated transistors are presented in this paper. The first topology is a high swing complementary regulated cascode active resistor. The second topology is a complementary common gate with a regulated cross coupled transistor. The small-signal input resistances of the floating resistors are derived. Three graphs of the input current versus the input voltage for different aspect ratios are designed and plotted using the Cadence Spectre 0.18-µm Rohm Semiconductor process. The total harmonic distortion graphs are plotted for three different aspect ratios with different input-voltage amplitudes and different input frequencies. From the simulation results, it is observed that a resistance of approximately 8.52 MΩ can be obtained from supply voltage at ±0.9 V.

This paper proposes for the first time symbolic formula of the power spectrum of CMOS Cross Coupl... more This paper proposes for the first time symbolic formula of the power spectrum of CMOS Cross Couple Oscillator and its modified circuit. Many principles existed to derived power spectrum in microwave textbook such as impedance, admittance parameters, ABCD, H parameters, etc. It can be compared by graph of power spectrum which methodology is the best from the point of view of practical measurement setup such as condition of impedance parameter which used superposition of current to derived (its current injection at the other port of the circuit is zero, which is impossible in reality). Four graphs of impedance parameters of cross couple oscillator are proposed. After that four graphs of scattering parameters of CMOS cross coupled oscillator will be shown.

2020 20th International Conference on Control, Automation and Systems (ICCAS), 2020

TENCON 2018 - 2018 IEEE Region 10 Conference, 2018

It is well known that a frequency multipliers used a diode for a frequency multiplication. The in... more It is well known that a frequency multipliers used a diode for a frequency multiplication. The infinite harmonic can be generated using diode with a sinusoidal input signal. The output of the frequency multiplier can be seen as a modulated wave if it is not a good result. This paper presented the high frequency multiplier by cascading a diode with a high order bandpass amplifier multiple times. An analysis and design are derived and simulated by MATLAB by using a SPICE model from Renesas Corp datasheet and a Schottky diode model from Hewlett Packard Corp.

World Academy of Science, Engineering and Technology, International Journal of Electronics and Communication Engineering, 2017

Introduction: Educational staff services play a role in determining the quality of education. Ser... more Introduction: Educational staff services play a role in determining the quality of education. Service quality is able to provide satisfaction for students. Students who were satisfied with the perceived quality will develop student loyalty to the institution. The purpose of this study was to assess the effect of educational staff service quality with the satisfaction and loyalty of nursing students so that the educational institutions as service providers are able to provide the best service and survive in the midst of competition. Method: The study was an explanative survey with a cross-sectional design. Data collection was conducted using both quantitative (questionnaires) and qualitative (Focus Group discussion/FGD) methods. This study used proportional random sampling, with 110 students as samples. The variables in this research were customer expectations, perceived quality, student satisfaction and loyalty. The data was collected by a questionnaire and analyzed by linear regression, while FGD was conducted in two different groups (students and staff's managers). Result: The result of the study explains the influence of student expectations on the perceived quality of the educational staff with a p-value = 0,002. There was no influence of student expectation on student satisfaction with a p-value = 0,156. The influence of the perceived quality of the educational staff towards student satisfaction had a p-value = 0,000. The influence of student satisfaction on student loyalty had a p-value = 0,000. Conclusion: The fulfilment of student expectations will have a positive impact on perceived quality. Furthermore, the positively perceived quality will create student satisfaction and student loyalty towards the educational institutions. For further research, it is suggested to examine the effect of satisfaction on student complaints.

Analog-digital mixed signal LSI plays an important role in the electronics. However, various on-c... more Analog-digital mixed signal LSI plays an important role in the electronics. However, various on-chip analog circuit designs have various tradeoffs and it is difficult to design. A filter and an oscillator are indispensable analog circuits. The active filter is important for a wide range of fields, such as a channel selection filter for wireless LAN, as a notch filter for 50 Hz, 60 Hz power interference cancellation, communication and biomedical signal acquisition. In addition, the oscillator is a core element for wireless communication and a clock for digital synchronous circuit. Based on this background, this research is conducting analog circuit design while comparing analytic and simulation method. Chapter 1 is an introduction, the background of this research and the Gm-C filter design previously proposed are summarized and the problems of the conventional design are summarized Chapter 2 discusses about noise analysis of Nauta’s transconductance amplifier. Usually, noise analysis must be derived by sum of mean square noise current source which is multiplied by square of output resistance divided by dc voltage gain. Equivalent output noise voltage of high order Gm-C filter simulation results are presented. Chapter 3 discusses about how to design two types of Gm-C filter called 5th order GmC elliptic filter and 10th order Gm-C elliptic filter based on element substitution which can be design from cutoff frequency, impedance scaling and filter table. The simulation results indicate that 5th-order elliptic Gm-C Low Pass Filter(LPF) shows the cut-off frequency dropped to 21.88 MHz due to high-frequency small-signal parasitic capacitances. The maximum input amplitude is -5.46 dBm for Total Harmonic Distortion(THD) less than 1%. The output noise is at -168dB at input frequency 1MHz. Chapter 4 discusses about Notch filter. This thesis proposed 2nd , 4th and 6th order Notch filter for interference rejection at 50 Hz which is the same frequency from high voltage power line. The architecture of 2nd order Notch filter from Kenneth Laker is chosen and designed. Magnitude response of 6th order Notch filter is simulated for 0.18 micron CMOS Process. The resistors in this block diagram can be substituted by floating active resistor if the notch filter is designed with very low cutoff frequency such as 50 Hz or 60 Hz, then, floating resistor is designed in the range of mega ohm which consumed very big layout area. For higher order notch filter, the theory is reviewed how to transform nth order of LPF LCR prototype into 2nth order of the notch filter LCR prototype. After the passive element value are computed from LCR prototype. Then, ground and floating active inductor can be designed from the value of the computed inductor value. Also, the biomedical signal acquisition LSI system is designed by modification of Twin-T 2nd order notch filter. Chapter 5 discusses about cross coupled oscillator design using Root Locus methodology. The time domain graph is shown as the result of four pole positions and four unknown constants which can be derived. The novel partial fraction expansion by multiplication of the factor denominator polynomial from the left side of the equation to the right side of the equation which is the conventional partial expansion instead of using the limit theorem. The fourth order polynomial can be factorized to have four pole frequencies. After that, the four unknowns can be computed by substituting the drain current into MATLAB file which are a function of the small signal parameters and passive element value such as capacitors, inductors and resistors. Usually, from simulation of the equations, the four unknowns are complex numbers. Thus, the solution of the four summation of term with each four unknowns has its own single poles can have four terms per unknowns because one unknown has real part and imaginary part and single pole can be exponential of complex number which can be expanded into real cosine plus or minus with imaginary sinusoidal function. It is found that from varying the time by using the period which is related with the oscillation frequency. The triangular wave waveform can be plotted as two graphs because underdamped real function has eight terms and underdamped imaginary function. Chapter 6 is a conclusion of the thesis.

The input impedance of a regulated cascode cross couple amplifier is derived. The frequency respo... more The input impedance of a regulated cascode cross couple amplifier is derived. The frequency response of the input impedance polynomial form can be plotted with MATLAB. From the polynomial form of the input impedance of the proposed circuit, it can be transformed by substitute complex frequency s with jω into the polynomial form equation. After that, this function can be grouped into a symbolic real and a symbolic imaginary form. The next step in derivation is to multiply this function with a complex conjugate function of the symbolic complex form of the input impedance. The last step is to plot a real and an imaginary part as a function of the input frequency so that the power amplifier can be matching with the various matching circuit according to the condition of the maximum power transfer.

International Journal of Circuits, Systems and Signal Processing, 2021

The polynomial form of the input impedance of a CMOS cross-coupled amplifier with NMOS only activ... more The polynomial form of the input impedance of a CMOS cross-coupled amplifier with NMOS only active inductor are proposed. The formula of polynomial form and novel coefficients are programmed in Scilab and MATLAB so that the pole position of the fourth order polynomial can be found. From experience of a simple cross coupled oscillator design, the proposed circuit diagram may not oscillate as a triangular wave signal because the two poles are complex (underdamped case) but its real part could not be minimized to 0.001 so that it has a stable amplitude and additional two poles are real poles. The impulse sensitivity function (ISF) of the proposed circuit is derived for the first time so that it may be used to derive phase noise in the future.

2019 Research, Invention, and Innovation Congress (RI2C), 2019

This paper presents microwave sensor system for moisture content measurement of paddy in hopper s... more This paper presents microwave sensor system for moisture content measurement of paddy in hopper silo. The sensor utilizes near-field transmission measurement technique operating at 400-500-MHz implemented by using double dipole antenna fabricated on FR-4 substrate. This proposed system is installed at the bottom of the hopper silo to collect moisture content. The moister contents of paddy in hopper silo from 12%–30% are measured and characterized. The extracted moisture contents from the sensors in this paper show an agreement of higher than 93% as compared with the commercial instrument in rice mill. In the system testing, the detection system is installed besides the silo 50 ton. IoT system was used to collect the result such as moisture and temperature of the system.

It is well known that input impedance of cross couple oscillator circuit has a fourth order denom... more It is well known that input impedance of cross couple oscillator circuit has a fourth order denominator polynomial form in frequency domain. Thus, it is important to design pole frequency by symbolic formula so that it is oscillate as a sinusoidal signal. It should be noted that in order for cross couple to oscillate, all pole frequency should be position on imaginary axis only in pole zero diagram. The graph of time domain response is plotted by using inverse Laplace's transform of the four unknowns of the partial fraction solution which were derived.

2015 Science and Information Conference (SAI), 2015

This paper proposed single stage CMOS complementary regulated cascode distributed amplifier (CRCD... more This paper proposed single stage CMOS complementary regulated cascode distributed amplifier (CRCDA) based on inductive coupling technique. Usually, distributed amplifier is based on inductive coupling between gate and gate terminal of MOSFET and between drain and drain terminal of MOSFET. But this paper proposes some new idea, by combining inductive coupling with circuit technique called CRCDA. There are three floating silicon inductors in the proposed circuit and twelve nodes of interconnection in the layout hierarchy.

2007 International Symposium on Intelligent Signal Processing and Communication Systems, 2007

ABSTRACT A fully differential rail-rail input stage and class AB output stage with and without co... more ABSTRACT A fully differential rail-rail input stage and class AB output stage with and without common-mode feedback circuit are proposed. There are at least 4 schematics to be proposed. The first schematic is CMOS rail-rail input stage and class AB output stage without common-mode feedback (CMFB) circuit. The second schematic is CMOS rail-rail input stage and class AB output stage with CMFB circuit. For low voltage operation, the tail current sources of the first and second schematics are removed. As a consequence, there is no voltage drop between drain and source terminals of the current source, and bulk-source voltage effect of the input transistor is removed.

The Fully differential operational amplifier (op-amp) schematics are compared in terms of specifi... more The Fully differential operational amplifier (op-amp) schematics are compared in terms of specifications such as unity gain frequency, current consumption. After choose LCR prototype, the proposed op-amp is used in 3rd order Butterworth response MOSFET-C lowpass filter. Simulation results using 0.35 um from TSMC corporation indicated that the proposed op-amp has an ability to have output signal swing from rail-rail (which means input output swings from positive to negative dc supply without distortion. MOSFET-C which used the proposed op-amp should have highest linearity if it is designed optimally. Figure of merit of fully differential op-amp is also proposed, this special specification of op-amp indicated that the proposed fully differential op-amp consumed least current at the same unity gain frequency compared with conventional schematics at least in simulation results. Experimental results from CMOS array of ALD1103, which is connected as fully differential op-amp, are used to ...

ISPEC2018 Technical-Digest, 2018

It is well known from communication system that ideal frequency modulator is the multiplication o... more It is well known from communication system that ideal frequency modulator is the multiplication of the carrier signal with information signal which can be model by cosine of the amplitude of sinusoidal of radio frequency signal. From this basic knowledge we can synthesize the circuit from this knowledge by using the exponential of the imaginary part of cosine of carrier signal plus or minus cosine of radio signal. By using bipolar junction transistor (low frequency or high frequency transistor). The collector current of the BJT can be solve as a function of the input carrier signal coupling with a capacitor or inductor and input radio frequency signal coupling with a capacitor or inductor so that the collector current can be a real part of the multiplication of both signal. After that, the collector current signal can be transformed by a 1 ohm resistor series with additional resistor so that it can be transformed into voltage at the anode of the additional diode or LED . The cathode of the diode or LED can be biased with resistive voltage divider. The output signal at the cathode of the diode can be cascade with operational amplifier to make an output. For the fully differential fm, the unknown supply voltage variable can be canceled with difference amplifier.

Tencon, 2018

It is well known that a frequency multipliers used a diode for a frequency multiplication. The in... more It is well known that a frequency multipliers used a diode for a frequency multiplication. The infinite harmonic can be generated using diode with a sinusoidal input signal. The output of the frequency multiplier can be seen as a modulated wave if it is not a good result. This paper presented the high frequency multiplier by cascading a diode with a high order bandpass amplifier multiple times. An analysis and design are derived and simulated by MATLAB by using a SPICE model from Renesas Corp datasheet and a Schottky diode model from Hewlett Packard Corp.

A fully differential rail-rail input stage and class AB output stage with and without common-mode... more A fully differential rail-rail input stage and class AB output stage with and without common-mode feedback circuit are proposed. There are at least 4 schematics to be proposed. The first schematic is CMOS rail-rail input stage and class AB output stage without common-mode feedback (CMFB) circuit. The second schematic is CMOS rail-rail input stage and class AB output stage with CMFB circuit. For low voltage operation, the tail current sources of the first and second schematics are removed. As a consequence, there is no voltage drop between drain and source terminals of the current source, and bulk-source voltage effect of the input transistor is removed.

—This paper proposed single stage CMOS complementary regulated cascode distributed amplifier (CRC... more —This paper proposed single stage CMOS complementary regulated cascode distributed amplifier (CRCDA) based on inductive coupling technique. Usually, distributed amplifier is based on inductive coupling between gate and gate terminal of MOSFET and between drain and drain terminal of MOSFET. But this paper proposes some new idea, by combining inductive coupling with circuit technique called CRCDA. There are three floating silicon inductors in the proposed circuit and twelve nodes of interconnection in the layout hierarchy. Keywords—CMOS regulated cascode distributed bandpass amplifier; silicon transformer modeling with polynomial

The Fully differential operational amplifier (op-amp) schematics are compared in terms of specifi... more The Fully differential operational amplifier (op-amp) schematics are compared in terms of specifications such as unity gain frequency, current consumption. After choose LCR prototype, the proposed op-amp is used in 3 rd order Butterworth response MOSFET-C lowpass filter. Simulation results using 0.35 um from TSMC corporation indicated that the proposed op-amp has an ability to have output signal swing from rail-rail (which means input output swings from positive to negative dc supply without distortion. MOSFET-C which used the proposed op-amp should have highest linearity if it is designed optimally. Figure of merit of fully differential op-amp is also proposed, this special specification of op-amp indicated that the proposed fully differential op-amp consumed least current at the same unity gain frequency compared with conventional schematics at least in simulation results. Experimental results from CMOS array of ALD1103, which is connected as fully differential op-amp, are used to compared with simulation results to supported the claimed.

ISPEC2018 Technical Digest, 2018

It is well known that a Frequency Modulator was invented by Edwin Armstrong since December 1933. ... more It is well known that a Frequency Modulator was invented by Edwin Armstrong since December 1933. Before the F.. M. Modulator
was shown in public, the theory of frequency modulation was written by John R. Carson since February 1922 [1]. The theory of
frequency modulation was also written by the differential equation by Van der Pol since July 1930 [2]. The block diagram and circuit
diagram of the F.M. receiver and transmitter were published by Armstrong since May 1936 [3]. The operation of the frequency
modulator was well described by him without the equation. The compact frequency modulator is proposed in this paper which is a
modified version of Colpitts oscillator circuit. It is observed that the collector current of the BJT transistor is a function of the base
emitter voltage drop. Thus, it is advantageous to transform real signal in time domain by using the passive element such as a passive
capacitor and passive inductor to time derivative of inductive current and time derivative of the voltage drop between carrier signal
and dc based terminal bias. This current can be seen as an imaginary current in the frequency domain. The emitter terminal is
injected by the radio frequency signal or speech signal or video signal which has an amplitude as a function of a variable called time.
For easy understanding, the radio frequency signal can be generated from the circuit called inverse hyperbolic tangent which is
unknown circuit but the concept of that circuit was shown in textbook of Prof. Paul Gray [4]. The block diagram of the recent
frequency modulator based on PLL circuit was proposed since 1990 by Kajiwara [5].