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unit 1 – construction of logic gates
unit 1 – construction of logic gates

... Input current for CMOS are low compared to output current TTL  no prob. Input voltage for CMOS are higher than output voltage ...
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE)
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE)

Power and Efficiency Measurement in a Thermoelectric Generator
Power and Efficiency Measurement in a Thermoelectric Generator

... have no moving parts and can have a relatively long life which is a benefit. However, thermoelectric generators have lower efficiency when compared to many other power generation devices. Thermoelectric generators can be used in engineering applications ranging from automotive waste heat recovery1 t ...
AD1580 数据手册DataSheet 下载
AD1580 数据手册DataSheet 下载

Sistem Mikroprosesor II - Yogyakarta State University
Sistem Mikroprosesor II - Yogyakarta State University

... converter (ADC). The controller could be equipped with an integrated ADC or an analog comparator [the Atmega 8 has both (?)] , which is used under software control to perform A-to-D conversion. ADC’s are used to acquire senor data from devices such as temperature sensors and photocells. Such sensors ...
Role of pi and fuzzy controllers in unified power quality conditioner
Role of pi and fuzzy controllers in unified power quality conditioner

... rather than a frequency domain approach. The most effective way to import the distortive power factor in a non-sinusoidal situation is to use a nonlinear active device that directly compensates for the load current distortion. The performance of these active filters is based on three basic design cr ...
Evaluates: MAX2181 MAX2181 Evaluation Kit
Evaluates: MAX2181 MAX2181 Evaluation Kit

... Noise figure can be measured using a NF meter. Because of the large number of FM broadcast signals that might be present, this measurement should take place with the EV kit in a screen box or other type of RF shield. ...
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3ème conférence Internationale des énergies renouvelables CIER

... Double-fed induction generators (DFIG) are gaining more attention especially in the field of wind power generation due to rapid development in power electronics. Variablespeed wind-energy conversion system using DFIG, fed with variable frequency rotor voltage allows fixed-frequency electric power ge ...
singhper1997 - EPrints@IIT Delhi
singhper1997 - EPrints@IIT Delhi

... used wherever possible by making use of the symmetry etc. For example, in a three phase balanced system, sensing of 3-phase voltage and current is made only for two phases and from these the required quantity for the third phase are derived. (3)Further reduction in the number of sensors used for sen ...
RA33H1516M1
RA33H1516M1

... sufficient to guarantee the level of reliability typically deemed necessary for critical communications elements. Examples of critical communications elements would include transmitters for base station applications and fixed station applications that operate with long term continuous transmission a ...
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ADM1184 数据手册DataSheet 下载

LM3670 - Texas Instruments
LM3670 - Texas Instruments

... either a single Li-Ion or three-cell NiMH/NiCd battery to portable devices such as cell phones and PDAs. Using a voltage mode architecture with synchronous rectification, the LM3670 can deliver up to 350 mA depending on the input voltage and output voltage (voltage head room), and the inductor chose ...
Novel Circuit Breaker Modeling in 275kV Substation Hamid Radmanesh Razieh Salimi Atani
Novel Circuit Breaker Modeling in 275kV Substation Hamid Radmanesh Razieh Salimi Atani

... reason of occurrence ferroresonance in transformers is described. Then various types of ferroresonance in voltage transformer in the case of considering novel model of circuit breaker are explained. Then general introducing of controlling ferroresonance by considering neutral earth resistance in the ...
All-solid-state, tunable, single-frequency source of yellow light for
All-solid-state, tunable, single-frequency source of yellow light for

... Among OPOs, DROs are highly sensitive to disturbances and therefore often are viewed as impractical for applications. However, with an appropriate cavity-length control system, high stability can be achieved with operation on a single mode pair without mode hops in excess of 10 h.8,9 As a consequenc ...
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Hybrid Multilevel Power Conversion System: A Competitive Solution for High-Power Applications

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DFW Series Wig-Wag Flasher

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Power Amplifiers - Learn About Electronics

... 25°C. The case temperature can only be allowed to rise to 150°C (the same as the maximum junction temperature) if the power dissipation is zero. Parallel Transistors for High Power Applications ...
When the output voltage increases
When the output voltage increases

... The series element controls the amount of the input voltage that gets to the output. If the output voltage increases (or decreases), the comparator circuit provides a control signal to cause the series control element to decrease (or increase) the amount of the output voltage. ...
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Lab Information -- Direct Current Machine Experiments

Chapter 18 Quiet Converter Design Dr.
Chapter 18 Quiet Converter Design Dr.

Inverter
Inverter

... are so small that they can usually be neglected and can be considered to be zero. It is important to remember this important approximation of zero input currents. Do not think that because the input currents can be considered to be zero the current in the output line is zero. The output current is s ...
Comparing Buck Converter Topologies
Comparing Buck Converter Topologies

... difference between the feedback signal and reference voltage. The rising slope of the inductor current is compared with the output of the error amplifier and when the inductor current exceeds the error amplifier voltage, the upper MOSFET is switched off. The inductor current then flows via the lower ...
1. Introduction - About the journal
1. Introduction - About the journal

... Once the carrier-signal at the desired frequency has been generated, it is divided in two equal parts, i.e. two signals with half of the original power and with the same phase are produced. To this purpose a broadband power divider is adopted [4]. The first output of the power divider is exploited a ...
10kV High Voltage Interface Brochure
10kV High Voltage Interface Brochure

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Pulse-width modulation



Pulse-width modulation (PWM), or pulse-duration modulation (PDM), is a modulation technique used to encode a message into a pulsing signal. Although this modulation technique can be used to encode information for transmission, its main use is to allow the control of the power supplied to electrical devices, especially to inertial loads such as motors. In addition, PWM is one of the two principal algorithms used in photovoltaic solar battery chargers, the other being MPPT.The average value of voltage (and current) fed to the load is controlled by turning the switch between supply and load on and off at a fast rate. The longer the switch is on compared to the off periods, the higher the total power supplied to the load.The PWM switching frequency has to be much higher than what would affect the load (the device that uses the power), which is to say that the resultant waveform perceived by the load must be as smooth as possible. Typically switching has to be done several times a minute in an electric stove, 120 Hz in a lamp dimmer, from few kilohertz (kHz) to tens of kHz for a motor drive and well into the tens or hundreds of kHz in audio amplifiers and computer power supplies.The term duty cycle describes the proportion of 'on' time to the regular interval or 'period' of time; a low duty cycle corresponds to low power, because the power is off for most of the time. Duty cycle is expressed in percent, 100% being fully on.The main advantage of PWM is that power loss in the switching devices is very low. When a switch is off there is practically no current, and when it is on and power is being transferred to the load, there is almost no voltage drop across the switch. Power loss, being the product of voltage and current, is thus in both cases close to zero. PWM also works well with digital controls, which, because of their on/off nature, can easily set the needed duty cycle.PWM has also been used in certain communication systems where its duty cycle has been used to convey information over a communications channel.
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