In this communication we propose a method to implement an all-optical astable multivibrator using the non-linear material based switches and logic gates. The scheme can operate in real time. The delay time can achieve...In this communication we propose a method to implement an all-optical astable multivibrator using the non-linear material based switches and logic gates. The scheme can operate in real time. The delay time can achieve ps(pico-second). The pulse duration can be made very low and may cross the THz easily by selecting proper material and laser source.展开更多
An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with d...An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with duty-cycle equaling 50%. The latch-up effect has been prevented on the improved circuit. It is extremely important that all the excellent performances of the improved astable multivibrator have been achieved with a dynamic power consumption equaling its predecessor one. The advantage of the structure has been verified by SPICE simulation.展开更多
The design and development of a timer based revolution per minute(RPM)measurement system were described in this paper.The rotating shaft of a dc motor was used to measure the RPM and timer integrated circuit(IC)555 wa...The design and development of a timer based revolution per minute(RPM)measurement system were described in this paper.The rotating shaft of a dc motor was used to measure the RPM and timer integrated circuit(IC)555 was used in astable mode.The frequency of timer output waveform measured by a digital storage oscilloscope(DSO)is almost linearly proportional to the RPM of rotating shaft,and the RPM also linearly varies with the change of the external input voltage level.Hence the linear relationship between the frequency of timer output waveform and the RPM can be obtained.The main advantages of this developed system are linear input-output relationship,small size,easy to carry and cost effective.展开更多
In this research paper,we have presented variable area type capacitive sensor signal conditioning system for angular displacement measurement and for this purpose we have used timer LM555 based astable multivibrator a...In this research paper,we have presented variable area type capacitive sensor signal conditioning system for angular displacement measurement and for this purpose we have used timer LM555 based astable multivibrator and universal frequency to digital converter (UFDC). Due to variation in angular displacement in the variable area type capacitor which is connected in the timer based astable circuit,capacitance changes which in turn changes the time period of the timer circuit output. The time period of the timer output waveform is linear with the capacitance and hence linear with angular displacement. The timer output is further processed with UFDC for the measurement. The experimental results show that the time period is linear with the angular displacement in the range of 0- 180° and the uncertainty we should associate it with this average time period value is the standard deviation of the mean,often called the standard error (SE),which is ± 0.023 μs. Because of the simplicity,this measurement system can be used in both electronic and industrial instrumentation.展开更多
This paper describes the development of a timer based voltage to frequency converter(V FC).Timer LM555is used in astable multivibrator mode with two OPTO-LDRs(light dependent resistors)in the circuitry.The frequency o...This paper describes the development of a timer based voltage to frequency converter(V FC).Timer LM555is used in astable multivibrator mode with two OPTO-LDRs(light dependent resistors)in the circuitry.The frequency of timer output waveform which is measured using a digital storage oscillator(DSO)is almost linearly proportional to the applied input voltage.Hence we obtain a linear relationship between the frequency of timer output waveform and the input voltage.Because of its quasi-digital output,the main advantages of this developed converter are linear input-output relationship,small size,easy portabilityand high cost performance.In addition,the timer output waveform can be directly interfaced with personal computer or microprocessor/microcontroller for further processing of the input voltage signal without intervening any analog-to-digital converter(ADC).展开更多
In this paper, current differencing buffered amplifier (CDBA) based bistable multivibrators are introduced. Each presented circuit is constructed using single CDBA as the basic active building block and three resistor...In this paper, current differencing buffered amplifier (CDBA) based bistable multivibrators are introduced. Each presented circuit is constructed using single CDBA as the basic active building block and three resistors. Two applications namely an astable and a monostable multivibrator are also realized to demonstrate the usefulness of the proposed bistable multivibrators. The presented circuits are simulated using PSPICE from Cadence Orcad16.2 to verify their functionality. Simulation results agree well with the theoretical analysis.展开更多
文摘In this communication we propose a method to implement an all-optical astable multivibrator using the non-linear material based switches and logic gates. The scheme can operate in real time. The delay time can achieve ps(pico-second). The pulse duration can be made very low and may cross the THz easily by selecting proper material and laser source.
文摘An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with duty-cycle equaling 50%. The latch-up effect has been prevented on the improved circuit. It is extremely important that all the excellent performances of the improved astable multivibrator have been achieved with a dynamic power consumption equaling its predecessor one. The advantage of the structure has been verified by SPICE simulation.
文摘The design and development of a timer based revolution per minute(RPM)measurement system were described in this paper.The rotating shaft of a dc motor was used to measure the RPM and timer integrated circuit(IC)555 was used in astable mode.The frequency of timer output waveform measured by a digital storage oscilloscope(DSO)is almost linearly proportional to the RPM of rotating shaft,and the RPM also linearly varies with the change of the external input voltage level.Hence the linear relationship between the frequency of timer output waveform and the RPM can be obtained.The main advantages of this developed system are linear input-output relationship,small size,easy to carry and cost effective.
文摘In this research paper,we have presented variable area type capacitive sensor signal conditioning system for angular displacement measurement and for this purpose we have used timer LM555 based astable multivibrator and universal frequency to digital converter (UFDC). Due to variation in angular displacement in the variable area type capacitor which is connected in the timer based astable circuit,capacitance changes which in turn changes the time period of the timer circuit output. The time period of the timer output waveform is linear with the capacitance and hence linear with angular displacement. The timer output is further processed with UFDC for the measurement. The experimental results show that the time period is linear with the angular displacement in the range of 0- 180° and the uncertainty we should associate it with this average time period value is the standard deviation of the mean,often called the standard error (SE),which is ± 0.023 μs. Because of the simplicity,this measurement system can be used in both electronic and industrial instrumentation.
文摘This paper describes the development of a timer based voltage to frequency converter(V FC).Timer LM555is used in astable multivibrator mode with two OPTO-LDRs(light dependent resistors)in the circuitry.The frequency of timer output waveform which is measured using a digital storage oscillator(DSO)is almost linearly proportional to the applied input voltage.Hence we obtain a linear relationship between the frequency of timer output waveform and the input voltage.Because of its quasi-digital output,the main advantages of this developed converter are linear input-output relationship,small size,easy portabilityand high cost performance.In addition,the timer output waveform can be directly interfaced with personal computer or microprocessor/microcontroller for further processing of the input voltage signal without intervening any analog-to-digital converter(ADC).
文摘In this paper, current differencing buffered amplifier (CDBA) based bistable multivibrators are introduced. Each presented circuit is constructed using single CDBA as the basic active building block and three resistors. Two applications namely an astable and a monostable multivibrator are also realized to demonstrate the usefulness of the proposed bistable multivibrators. The presented circuits are simulated using PSPICE from Cadence Orcad16.2 to verify their functionality. Simulation results agree well with the theoretical analysis.
