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    What is power rail

    Generally we use the term power supply, but sometimes i also see the term power rail being used. What is the difference? When should i say power rail and when power supply?
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    Circuit Analysis of Opamp Ckt

    i am trying to analyze the below circuit It is part of the actual and bigger schematic. I tried to simplify the circuit as below, i am not sure of the effect of capacitor C1 hence as first step i removed it and analyzed Assuming ideal op amp configuration V+=V-, I+ = I-=0; And let V0 be the...
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    Voltage Divider Bias BJT clarifications

    I am studying the voltage divider biasing of a transistor. I came across few terms which i do not understand."When the emitter resistor is viewed from the base circuit, the resistor appears to be larger than its actual value because of the dc current gain in the transistor. That is RIN(Base) =...
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    Calculate Transistor Parameters

    I need to calculate IB,IE and IC with Alpha(DC) = 0.98 for the below circuit I generally did problems with some base resistor and collector resistance and here i don't find both. I did the following attempt Since VBB > 0.7V the BE is forward biased (current required?) If i consider the...
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    Transistor Power Dissipation

    When i observe the datasheets of some of the transistors, i only see the dissipation at the collector mentioned, but there will be some dissipation at the base of the transistor as well? Why it is not mentioned? That may be because it is very low, but when i do some calculations for transistors...
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    Large Currents vs Small Currents

    I want to know is it possible to distinguish between large currents and small currents. For example beyond certain Amps (ex. 1 Amp) it is called large current and below this it is small current etc? Is there is any such definition?
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    Few Clarifications on the IR2181

    Trying to decode the complete motor circuit from microchip and this is a continuation of the previous thread started, understanding the circuit related the IR2181 high side MOSFET driver. The screen shot of the circuit is below and i have attached the complete circuit. If i see the data...
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    What is the use of IC 74ACT244MTCX (dsPICDEM MCLV-2 development board)

    I have seen IC 74ACT244MTCX as a part of motor control circuit. I downloaded the data sheet and found as Line driver and when try to understand, i only see lot of tables and it is difficult grasp information. What is this IC, why do i need to use this?
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    Operating range of the devices

    I observed for every device there is an operating range specified (ex:IC, individual components and system) by the minimum voltage and the maximum voltage. My understanding as per this specification is that for every device there is a fixed resistance for example R, if the minimum voltage is...
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    How long a motor can run

    If i take a synchronous motor and operate under the normal operating conditions and within its limits, Can i run the motor continuously like 24*7 or it is always required that it be stopped in between the operation to allow it to cool? If i keep operating the motor and provide the necessary...
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    Space Vector Modulation

    I am referring to the document attached and referring to the page 13, the svpwm is as below The document refers to the inverter with SVPWM applied, the input voltage is the Vdc to the inverter and when i observe the voltage output to the motor after svpwm is . I know this a sine wave...
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    Clarifications on the PWM signal

    I have few clarifications on the pwm signal very basic ones a. If my input voltage is let us say 5V and the output contains resistor. Now i control this 5V signal using a pwm of 50% duty, then at the output do i measure 2.5V (5/2 V) or the RMS value? For sine wave it is the RMS values, so i...
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    Does Inductor and Capacitor get heated

    Does inductor and capacitor get heated, why i am asking is the capacitor and inductor stores energy and it returns back but there is no dissipation, in case of resistor it dissipates energy and it gets heated that i understand.
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    Balanced 3 phase system

    I have few clarifications with the 3 phase balanced system. Does a balanced 3 phased system mean that the impedance's Z1 = Z2 = Z3 is the only condition? because during that case the current through the Neutral is 0 else there is some current flowing through Neutral. Few other questions on...
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    DC-DC converter design

    For a long time i am thinking of designing circuits on my own. So, just as beginning circuit i am trying Dc-Dc circuit and converting the 20V to 5V, because i come across dc-dc conversion very frequently. Below is the circuit i tried i have drawn a resistor divider network and after...
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    Difference between Phase and Line

    When I am reading 3 phase systems, i very frequently listen the terms phase and line. Both of them almost look similar but yes there are differences. What is the exact definition and are there any shortcuts which can help me to easily remember a phase and a line?
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    Determining the source voltage

    This the circuit i am trying to solve, I need to find the voltage e1 My work is like e1 + e2 = v -> Applying the Kirchoff's Voltage Law e1 = v - e2; But the answer does not seem to match. What is the mistake? Note: small clarification, can I use latex here?
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    Direction of Current in AC circuits.

    I am confused with the direction of current for AC circuits, for example if i consider the below circuit My main concern here the direction of current is shown going from -Ve to +Ve and the source is the AC signal. Q1. Will the direction of current will always be the same as shown in the...
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    How to identify lead or lag on oscilloscope

    I am trying to understand the lead and lag on an oscilloscope, this is one of the images explained in the book I understood that the phase difference is 144deg as it is 2 divisions and the complete cycle is 5 divisions for 360 Deg. I am only confused how to identify the lead and lag, the book...
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    9V Battery ground and Power supply ground

    I want to know the difference between the 9V battery negative (can it be called the ground?) and the power supply ground? The 9V battery has negative terminal is it same as the source ground which is connected to the mains.
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