Recent content by CoolDude420

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    Sources of voltage ripple in buck converter

    Why do you need an ESR for the capacitor to create a voltage ripple? Just the capacitor on its own receiving the AC component of the inductor current will charge it up, thereby creating a voltage ripple.
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    Sources of voltage ripple in buck converter

    I think I am getting confused between voltage ripple and current ripple. The LC filter will severely attenuate voltage ripple at the switching frequency and the harmonics, for any bit of voltage ripple left over, we use the small-ripple approximation and say it is zero. However, the current...
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    Sources of voltage ripple in buck converter

    I am reading a book 'Fundamentals of Power Electronics' - Erickson. The book begins with a buck converter and the assumptions that we use so that we do not have to deal with 2nd order equations. I will first explain what the book says What the book says? The book says that the LC filter of a...
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    Why is current defined as the rate of change of charge?

    Sorry, I apologies for not posting correctly. Fundamentals of Electric Circuits Book
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    Why is current defined as the rate of change of charge?

    Homework Statement:: This isn't a homework question but just a theoretical questions. [mentor’s note: moved to a more appropriate forum for theoretical questions.] I know that current is defined as the rate of change of charge per unit time. i = dq/dt This makes sense for a capacitor which...
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    Engineering Depletion region capacitance in MOSFET

    I would like to ask about the behavior of a MOSFET as a capacitor, particularly at the onset of inversion/weak inversion - see Fig 2.6(c) At this stage in Fig 2.6(c), there is positive charge at the gate metal/poly contact, then an insulator oxide and then negative ions (positive holes have...
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    How are holes charge carriers?

    Homework Statement:: Hi, It's been a while since I have reviewed my basic semiconductor physics and I have some doubts. In a P-Type doped semidoncutor material, I understand that Group III elements such as Boron are added to a Group IV element such as Silicon and thus the Boron atom has one...
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    Engineering Charge Redistribution in a Capacitor Bank/DAC

    Thanks very much. One last thing, the voltage on Vref should always decrease right? Even in the case where we switch capacitor C1 from Vref to GND (rather than C2 from GND to Vref) and leave everything else the same.
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    Engineering Calculating the size of a capacitor in a sample and hold circuit

    First, I calculate the jitter power with an equation given in the book Next, I calculate the signal power Now, I know that SNR = Psignal/(Pjitter + PthermalNoise), However, I seem to be getting a negative value for the thermal noise power?? My plan was to use this thermal noise power and...
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    Engineering Charge Redistribution in a Capacitor Bank/DAC

    Also, shouldn't C123 = C1 +C2 +C3 = 32fF + 32fF + 16fF = 80fF rather than 64fF?
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    Engineering Charge Redistribution in a Capacitor Bank/DAC

    Ah, I see. Let me try it by hand now. Also, side question. Is there any way to use charge redistirbution to do this? I thought that charge redistribution always applies. I tried it with my method that I stated in a previous post, answers look reasonable except they go in a opposite direction...
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    Engineering Charge Redistribution in a Capacitor Bank/DAC

    Why is V123 = 2Vin - Vref? I understand the Vin-Vref voltage is what capacitors C1 and C3 had in the start and after. I also understand that as soon as you switch (at time t = t0+), that capacitor C2 still has voltage Vin across it, yet it is now in parallel with C1 and C3. Why are you adding...
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