Medium voltage range energy harvester application using boost converter

Energy obtained from the surrounding is usually very low and scarce. Such energy can be found from the vibration, solar and heat to name few. Often this energy is less than 1.5 V. Based on this motivation, DC-DC boost converter circuit is choose and design to convert low energy to sufficient amount to be used in normal circuit device and system application. This paper introduces a medium range output voltage using conventional DC-DC boost converter for low input supply range. Simulation has been done and compared with the experiment results. The purpose of this paper is to show the possibility of conversion very low energy to up to 50 V and to discuss a brief operation involved. A linear 4 V to 49 V output voltage trend was obtained from the experiment, under low switching frequency, 2 kHz. The targeted input used in this paper is between 0.1 V to 1.5 V suitable for energy harvesting purpose

Parasitic consideration for differential capacitive sensor

Parasitic integration for a single supply differential capacitive sensing technique is presented in this paper. In real capacitive sensor measurement, parasitic impedance exists in its measurement. This paper objective is to study the effect of capacitive and resistive parasitic to the capacitive sensor circuit. The differential capacitive sensor circuit derivation theory is elaborated first. Then, comparison is made using simulation. Test was carried out using frequency from 40 kHz up to 400 kHz. Result is presented and have shown good linearity of 0.99984 at 300 kHz, R-squared value. This capacitive sensor is expected to be used for energy harvesting application

A DC-DC circuit using boost converter for low voltage energy harvesting application

A DC-DC step-up voltage converter is designed to convert a very lowvoltage supply, 35 mV such as fromthe thermal energy source from body heat. The converter can generate an outputvoltage up to 210 mV, approximately six imes its initial input voltage over afrequency of 36 GHz. The effect of switching transistors, inductor current,rise and fall time is also highlighted. The circuit operates using 2 µH inductor and 0.01 fF load capacitor, is simulated usingPSpice Simulation tool. This voltage converter is suitable for energyharvesting application in implanted electronic devices

Linearization circuit for transducers for nonlinear reponses

Thermistors are nonlinear transducers, and have found wide application in temperature measurement and control in different fields, but they exhibit a strong nonlinearity of the characteristic, which is of an exponential type. This project investigates the possibility of creating a thermistor-based temperature sensor with frequency and analog outputs and a linearized characteristic on the basis of a 555 timer

Parametric sweep analysis of medium voltage range boost converter for energy harvester application

This paper presents a parametric sweep analysis discussion on proposed DC-DC boost converter circuit for low and wide voltage supply range. Analysis is initially done using computer simulation and then tested with experimental work. Results are combined and discussed in details. In this work, effect of parameter such as input voltage, switching frequency and inductance is presented in details. A linear conversion has been observed in this work. Low DC input voltage of 100 mV to 1.5 V is used and successfully converts to up to 50 V in linear inclination, considering CL = 10 µF, and RL = 10 kΩ. The circuit parameter for this voltage range are L = 100 µH, D = 50 %, and 2 kHz frequency operation. This circuit can be used for energy harvesting purpose and medium voltage application such as aircraft, wireless measurement system and automotive

Parametric analysis of single boost converter for energy harvester

This paper presents a conventional DC-DC boost converter for low and wide voltage supply range, suitable for energy harvesting purpose. The output voltage can be increased by controlling the transistor switching frequency, duty cycle,inductance, load capacitor, rise, and fall time. Both computer simulation and experiment results are performed in details. Experiment results have shown an error less than 6 % with the simulation. A linear trend of output voltage in the range of 4 V to 49 V is successfully converted from 100 mV to 1.5 V input voltage using low switching frequency of 2 kHz. The circuit parameter for this voltage range are L = 100 μH, D = 50 %, tr = tf = 2.9 μs considering CL = 10 μF, and RL = 10

Single supply differential capacitive sensor with energy harvester compatibility

This paper presents a single supply differential capacitive sensing technique suitable to be used with a hybrid energy harvester in providing power to the circuit. The proposed differential capacitive circuit is designed based on the available off-the-shelf components. Theoretical and experimental study has been carried out to observe the performance of the circuit for various excitation frequencies. Tests that were carried out include using excitation frequencies ranging with a 0.1 pF capacitance change. Results from 40 kHz up to 400 kHz show a high level of linearity up to a 0.999 R-squared value. Range of capacitance detection can be increased by controlling the feedback capacitor, Cf, and the filter components, Rd and Cd. The sensitivity range is from 0.004 to 0.122 mV per every fF change,with ± 5 % error. The circuit consumes 3.83 mW, with a 3.3 V supply voltage. This circuit is also suitable for a wireless sensing node application

Evaluation of a Hydrogel-Based Diagnostic Approach for the Point-of-Care Based Detection of Neisseria gonorrhoeae

Eleven primer pairs were developed for the identification of Neisseria gonorrhoeae. The sensitivity and specificity of these primers were evaluated by Real Time (RT)-PCR melt curve analyses with DNA from 145 N. gonorrhoeae isolates and 40 other Neisseria or non-Neisseria species. Three primer pairs were further evaluated in a hydrogel-based RT-PCR detection platform, using DNA extracted from 50 N. gonorrhoeae cultures. We observed 100% sensitivity and specificity in the hydrogel assay, confirming its potential as a point-of-care test (POCT) for N. gonorrhoeae diagnosis