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MURI Book 1. - SLAC Group/Department Public Websites
MURI Book 1. - SLAC Group/Department Public Websites

... Working with Professor Bill Hansen at the Stanford Physics Department, as Research Associates, were the Varian brothers, Russell, a physicist, and Sigurd, a former barnstormer and Pan-American pilot. “Sig” Varian believed that high-frequency transmitters could be used aboard airplanes to make “blind ...
Pulse and Pulse Processing
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... Pulse : Where are the information? Brief surges of current or voltage in which information may be contained in one or more of its characteristics – polarity, amplitude, shape etc. ...
LM2940QML 1A Low Dropout Regulator (Rev. B)
LM2940QML 1A Low Dropout Regulator (Rev. B)

... Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is functional, but do not ensure specific performance limits. For specified specifications and test conditions, see the Electrical Characteristics. The ens ...
ML Maximum Power Point Tracking (MPPT) Series Solar
ML Maximum Power Point Tracking (MPPT) Series Solar

... Maximum Power Point Tracking (MPPT) is an advanced charging technology that enables the solar panel to output more power by adjusting the electric module's operating status. Due to the nonlinearity of solar arrays, there exists a maximum energy output point (maximum power point) on their curves. Una ...
High-Precision, Low-Noise, Rail-to-Rail Output, 11MHz JFET Op Amp OPA140 OPA2140,
High-Precision, Low-Noise, Rail-to-Rail Output, 11MHz JFET Op Amp OPA140 OPA2140,

... Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those specified is not supported. Input ...
36-V, Prog.-Gain, Voltage-Output, Bidir, Zero
36-V, Prog.-Gain, Voltage-Output, Bidir, Zero

... Current-Shunt Monitor 1 Features ...
an electrothermally-driven low voltage micro switch for high
an electrothermally-driven low voltage micro switch for high

... thermoelectrostatic actuated shunt switch has been proposed and its complete dynamic operation explained. All its functional properties have been simulated through 3D finite element methods, and then high frequency parameters of the switch extracted. At the end, the fabrication process of the switch ...
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TL52055 数据资料 dataSheet 下载

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PDF document - eetasia.com

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External Cavity Diode Laser Controller

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Basic Trouble Shooting Motor/Solenoid Equalizer Hydraulic Pumps

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Impact of Leading Power Factor on Data Center Generator

Arc Guard Systems Arc monitor Current sensing unit Accessories
Arc Guard Systems Arc monitor Current sensing unit Accessories

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Linear Systems replaces discontinued Siliconix 2N4391

... Information furnished by Linear Integrated Systems and Micross Components is believed to be accurate and reliable. However, no responsibility is assumed for its use; nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implicati ...
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UPS003024024015 TO REDUCE THE RISK OF INJURY, USER MUST READ INSTRUCTION MANUAL

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2. electric motors - Bureau of Energy Efficiency
2. electric motors - Bureau of Energy Efficiency

... losses (sometimes called iron losses) consist of eddy current and hysteresis losses in the stator. They vary with the core material and geometry and with input voltage. Friction and windage losses are caused by friction in the bearings of the motor and aerodynamic losses associated with the ventilat ...
Avoiding Harmonic Resonance with Low Pass
Avoiding Harmonic Resonance with Low Pass

... voltages to be present. For series resonance, where the L and C components appear electrically in series with each other, XL=XC and therefore the combined impedance is very low. This means that if harmonic voltage is present at a frequency close to the resonant frequency, the harmonic current into t ...
Failure Mechanisms For Transient Voltage Suppressors
Failure Mechanisms For Transient Voltage Suppressors

... it ultimately breaks the glass body into two parts at the location of the active die element. To avoid these type failures, conservative selection in Ppp for TVSs beyond the expected threat level requirements will minimize these catastrophic failure modes. This includes consideration for Ppp tempera ...
A Noniterative Optimized Algorithm for Shunt Active Power Filter
A Noniterative Optimized Algorithm for Shunt Active Power Filter

... optimization-based approaches is the use of iterative techniques for solving the optimization problem. The use of an iterative technique can result in a computational delay, which can constrain the applicability of these control approaches under dynamic load conditions. As a result, the methods prop ...
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... Any device is based on a pre-assumption or have a fault tolerance or error margin. So digital circuits do have a margin of about 15% in lifetime [2]. These margin are denoted by C kp numbers and there are several factors that governs this number and these factors are Hot Carrier Degradation, Gate Di ...
Instruction Manual for A6000 Series Universal Digital Panel Meters
Instruction Manual for A6000 Series Universal Digital Panel Meters

... Each parameter of the A6000 has an individual protection level, and by setting the protection level of the condition data, you can set an access level. (For the protect level of each parameter, see the P.L. column of the tables in Section 4.5.) The higher the protection level is, the less the number ...
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HMC595 数据资料DataSheet下载

Direct Current Motors - Alfred State College intranet site
Direct Current Motors - Alfred State College intranet site

... n = 60 Es / Z Φ n = 60 Es / Z Φ This method is only recommended for small motors because a lot of power and heat is wasted in the rheostat, and the overall efficiency is low. ...
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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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