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How to drive a MOSFET from AC wih max efficiency?
Short version: if I needed to drive a MOSFET from mains AC, that will be switching (PWMing) mains AC as well, and needed to do this “fast and often”* how should I derive the power to drive it’s gate...
View Articlewhat is the real DC power dissipated by an inductor that is pulsed on off
A meter indicates a higher DC power being delivered to a circuit consisting of an inductor switched on and off by a MOSFET on both the high and low side, than the heat measured by a thermistor. The...
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Calculating the input current drawn by a MOSFET driver
I am using a PIC32MZ’s OC pins (PWM mode, fault disabled) as input to a dual MOSFET driver (ISL89163 A). I need one OC pin to drive 3 drivers i.e 6 inputs each. The pulse width would be around...
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I need some help understanding overshoot and ringing in MOSFET half bridges
From FDA75N28 datasheet: What I am having difficulty understanding are the reasons behind overshoot and ringing in V_DS. Now, to what I already know: The current that passes in an inductor cannot...
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How to do DC Analysis for a Common Source Biasing Circuit using NMOS
I am having a lot of trouble with this specific problem. I want to find Vg, Vd, Vs, and Id for this specific common source biasing circuit that has an NMOS. I have these values given: Vdd = 9V, k/2 =...
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Limit the current of a fixed voltage via MOSFET+PWM
I have a SMPS which I would like to current limit. The current limiter should have a negligible voltage drop when not limiting (say, <0.5%). I thought of inserting a MOSFET and a hall-effect current...
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What is the purpose of these extra 'level shifter' BJTs on a MOSFET H-Bridge?
I am working on a 2WD Arduino project. Making the H-Bridge myself, and not using an IC like the L293 is a requirement for my project. After searching a while, I came across this, and based on this I...
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Small signal model for Mosfet…unsure as to whether its common drain, gate or...
I am looking to solve for the input/output resistance in the small signal model for the below circuit. But, I am unsure as to how to set up the model as I can’t tell if it is common gate/source/or...
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N-Mosfet switch circuit strange behavior laboratory power supply
I’m dealing with an N-Mosfet switch circuit to control, through PWM, the temperature of a heater resistor. The mosfet is a IRFS7430-7PPBF. The load is driven at 12V and has a power rating of 80W. Since...
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Basic doubt regarding attached circuit
Could some one give me a quick answer why voltage drop at the drain of M1 is 4.611V and not 5V. Since the N-FET is non conducting, it acts as a open. similarly the diode should also be off and open....
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