Questions tagged [powermosfet]
The powermosfet tag has no usage guidance.
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What voltage will drive this MOSFET best?
I'm planning to use this MOSFET as on/off switches for various loads ranging from roughly 100 to 250VDC and 0.1 - 1A. I believe it to be more than adequately sized. I can also add quite a bit of ...
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MOSFET On/Off Switch Power Dissipation
Basic setup: A battery is discharged using some lightbulbs wired in parallel. At various points throughout the discharge cycle, lightbulbs are switched off in order to increase the resistance of the ...
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How does a bootstrap capacitor power the gate?
I understand this circuit for the most part, but I am still confused on something.
So lets say that the bootstrap capacitor is already charged from the bottom MOSFET being on previously. Then, a logic ...
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How is a highside gate powered with a bootstrap circuit and MOSFET driver?
I have been trying to understand this circuit, but I just don't get how the boot strapping works.
Correct me if I am wrong but if I apply 400V at the drain of the high side MOSFET, the gate needs 410V ...
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How is MOSFET gate resistor chosen?
I have been doing research on MOSFETS. I see that in a typical circuit that includes a MOSFET and a Driver IC, there is a gate resistor. I have done research on this gate resistor and I am aware that ...
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How to choose a MOSFET driver?
What do you look for in a MOSFET driver before choosing it to switch a certain MOSFET? Am reading through the driver datasheet and cant precisely understand what is the ability limit of this driver.
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Overvoltage Protection
I just destroyed my $1,500.00 wind turbine's battery charging module. I think I need a surge & overvoltage arrestor to add to my system to protect its replacement.
We have a small family farm in ...
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Using IRF7821PbF mosfet without a gate driver
I have extracted some information from the datasheet of the IRF7821PbF and would like some confirmation on it.
I calculated that if I have a 6A load, it only dissipates 0.32W and gets only 16° warmer ...
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Mitigating FET current spikes in an SMPS buck converter
I'm currently designing an SMPS buck converter that converts 311VDC to 60VDC at 10 Amps maximum load. I'm using ESP32 for the PWM control, and IR2110 for the switching driver. The switch I'm currently ...
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Formula to calc Id of this IRF3205 in the linear region from this specific voltage measure point
I was doing a project of a electronic load and I bought a hall effect sensor to measure the current through the mosfets in this project.
Due to some instability in the hall effect sensor, I needed to ...
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RLD + RC Snubber for MOSFET
I'm currently making a DC-DC SMPS power supply that converts 331VDC (rectified from 240VAC) to 60VDC with a maximum output current of 10 amps. I've asked once on this forum about a general problem on ...
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Inconsistent behavior of MOSFET gate driver
I am working on a 7-level power micro-inverter which composed mainly by power MOSFETs. These logic-level MOSFETs (IRLZ24NS) are driven by separate photovoltaic gate drivers with integrated fast turn-...
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All Mosfet terminals internally shorted in voltage controlled resistor
I was planning on making a voltage controlled resistor using a power MOSFET in order to load one 12V lead acid battery. I tried implementing the circuit below; everything was going well for a few ...
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Chain MOSFETs to drive high voltage / high power signal from 3V3 GPIO?
I have a set of LED light strips (LEDs + resistors integrated) that I want to control with MCU GPIO outputs. The MCU outputs 3V3 signals.
I have tested the IRBL8721 Power MOSFET and also the IRFZ44 (...
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Solenoid valve driver circuit [closed]
Which extra protection components should i use if my solenoid valve of rating 24V 1.7A is driven by the POWER MOSFET IRF540 controlled by Arduino? (Flywheeling diode is there.)
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Layout for MOSFETs (copper area for source vs drain)
I have a schematic. Here is a section of it:
The FETS are being driven by the chip to behave as ideal diodes. Plus two FETs in series to block current path when chip is in shut down stage.
I've seen ...
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P-Channel MOSFET - Vsd unexpectedly high when driven on?
Using this cct with a FQP27P06 P-Channel MOSFET. I am trying to switch 12V power on the high side to a non-inductive load drawing about 3A . I am expecting 0.07 ohms x 3 A = .21V drop across the ...
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CN3722 External MOSFET heating up
In my charging circuit, CN3722 is used as the charging controller where I'm using an external MOSFET FDS4435bz as per it's application. Earlier I was using DMG2307L-7 which was heating up(50°C). To ...
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MOSFET heats up quickly in High power 14V DC-DC bidirectional charging circuit
I am currently design the following circuit to charge a 14V LifePO4 4 cells battery while running a high power motor at 14V 24A. There are some issues that I am currently facing:
Without any diodes ...
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Automatic multiple switch ON when power is applied
I have made a switch as shown in the schematics to turn ON/OFF 24 loads. When I apply a pulse on the ON-signal the load gets 24 V and when an OFF-signal pulse is applied the 24 V at the load gets ...
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Sensing current into a battery while charging
I want to sense the current into a 84 V battery while charging and disconnect it when fully charged using a MOSFET. Is it advisable to use lowside current sensing? I used a noninverting opamp ...
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How to compute the SOA of a MOSFET?
Is there any tool to check if a MOSFET is within its SOA or not for a given operating condition?
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Power MOSFET gate driver: voltage and current levels
Following are the doubts on the gate driver section of a forward converter.
Peak drive voltage = 7.4 V (Shouldn't it be higher, say 10 V or so, usually for driving power MOSFETS?)
Peak MOSFET gate ...
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UCC27211 Gate Driver High Side Output Randomly Turns Off
I am operating a half bridge. The high side gate driver output randomly turns off. I am unable to identify why this may be happening. Attached is an image (Pink: HO, Cyan: HI, Green: LI, Blue: Vgs(LO)....
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Overheating P-CH MOSFET at Low-ish Current
I designed/had built a PCB to handle higher current draw. The P Channel MOSFET (Q1) I selected is used as a ON/OFF switch for the rest of the circuitry. R2 gets grounded through a switch when flipped ...
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MOSFET selection for buck regulator (SOA vs thermal dissipation)
I am trying to design a buck regulator with the following specification: Vin = 24V Vout = 5V I max = 8A Fsw=228k. The load is basically a long strip of RGB LED's. Which in certain cases would be all ...
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How to use MOSFET?
I'm having trouble understanding MOSFET.
There is always a voltage at the drain pin (my case: MOSFET on 5 V, MOSFET off 4.8 V).
I've tried n-channel irfz44n and p-channel irf4905, but the result is ...
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Ringing at input of digital isolator while driving a mosfet with high voltage and current
From a rectified main 230V supply + 4x120µF 400V capacitor, I'm driving a STW40N65M2 mosfet which commutes a big coil.
Gate is driven by MCP14A0304T. Gate current is limited by a 30.9 Ohm resistor. ...
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Voltage at the drain of P-channel part of IRF7319
Given the switch schematic:
When I applied 5V to VCC and pressed SW1, I measured 4.8V on the drain of Q1B.
With SW1 released, I measured 1.85V on the drain of Q1B.
I read that power MOSFETs require ...
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Why is a capacitor connected across the power MOSFET in the DC-DC stage of most SMPSs?
In many of the schematics of the DC-DC stage of SMPSs, there is an external capacitor connected across the MOSFET switch (across drain and source). Why is this capacitor required?
MOSFETs have an ...
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Why does the below SPICE simulation show an initial current even before the voltage source is applied?
LT-spice simulation is showing a sudden jump in MOSFET current from 0 to 5mA at t=0. What would be the explanation for this? Is it a tool issue?
All the capacitor initial voltages (C2, C1 and C4) are ...
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Low loss method of connecting two dissimilar battery voltages together without a diode?
TLDR; Is there a simple circuit which delivers a diode's robust reverse-voltage behavior, only with an order of magnitude less heat generation?
I have two lithium batteries with different chemistries ...
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Would this be an appropriate design for interfacing high-power LEDs with an ESP32?
I am currently exploring a project that allows me to control high-power RGB LEDs using PWM from an ESP32 microcontroller. In this way, I plan to create a simple LED panel for canopy illumination that ...
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High-Side P-Channel MOSFET for Lower Rated Toggle Switches
My goal is to add two toggle switches to high power DC lines so that I can break the circuit and stop power from being delivered to my load. This load will be using 28V, ~27A. I have an two channel ...
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Why does max current handling differ greatly form different MCU boards?
I had successfully controlled my power inverter using an Arduino DUE (Atmel SAM3X8E). To drive all of my six power MOSFETs (IRLZ24N) each GPIO is interfaced by a Photovoltaic MOSFET Driver (Panasonic ...
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FET Gate Voltage Question
What gate voltage is required to turn on a power MOSFET to the specified Rds(on) at a given drain current?
Take for example, 1.5A drain current using this FET. https://www.vishay.com/docs/78092/...
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MOSFET Vds is too high when MOSFET turn on
Few days ago, I upload question about MOSFET driver getting too hot.
That problem was solved by your help. thank you.
But I have another problem. I connect 80ohm load to MOSFET like this figure.
...
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Heatsink size calculation
Let's say I found a random heatsink with no name or model or anything else from which I can find a datasheet and get its thermal resistance. Therefore, simply by knowing its sizes, how can I calculate ...
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I don't know why UCC27324 getting hot in normal condition
I have some question about UCC27324P MOSFET driver.
I have experiment using UCC27324D (8-DIP type) and UCC27324P (SMD type) via this circuit.
DIP type driver works fine with no problem same condition.
...
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Is there MOFET with Id is between 10-14A at Vgs<4.2V? [closed]
I am new to the area of working with MOSFETs. For my current project I need a suitable MOSFET or any other transistor, that should work as a switch. My output controlling voltage from controller IC is ...
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Rated drain to source voltage of a power MOSFET sustaining back EMF of solenoid
I have an H-bridge that is using 4 n-channel MOSFETs with max rating of 500 V 100 A drain to source driving a large inductor/actuator reliably. I'd like to find a cheaper MOSFET since the 100 A is ...
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MOSFET failed when I connected an AC universal motor
I connected the following AC chopper circuit to control the brightness of a lamp and it is working as expected.
Expected behavior: I observe that when the pulse is 0, the light is completely off. When ...
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How should fuses be used for MOSFET temperature protection?
I am using high voltage MOSFET in TO-220 package with a heatsink like this one:
Under normal conditions, the temperature of heatsink does not exceed 90 degrees.
My MOSFET can run up to 120 degress ...
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What does the cross point of V-I curves mean?
Here you see a V-I graph including many curves achieved under different junction temperatures of an IGBT. As it can be seen there is a cross point where all curves intersect each other. Does it make ...
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Mitigating parasitic turn-on of MOSFET
UPDATE
Thanks Aaron and jp314 for your comments.
We just probed some more and I think jp314 is right.
We found that the high side driver was skipping some pulses. The pink pulse train is from the ...
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MOSFET back-to-back configuration
To build the back-to-back configuration using MOSFETs, must the second MOSFET be the same as the first or do I need a complementary MOSFET transistor like in BJT transistors? If I need a ...
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P Channel MOSFET gate controlled by N Channel MOSFET (rather than NPN). Crazy?
I needed a generalized circuit that would switch on/off any device on the Vcc side with varying voltage (3.3 to 24 V) and current (0 to ~10 A). A P Channel MOSFET is an obvious choice, but I didn't ...
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Can SiC SoA rating be extrapolated for faster pulse widths?
This datasheet for a Rohm SCT3017 silicon-carbide N-channel power MOSFET's Safe Operating Area only extends as fast as 100µs. Why no trace for 10µs?
Is it because with an expected gate charge of ...
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Sender Circuit for Ultrasound
I'm building this Instructables project: Body-ultrasound Sonography With Arduino, which is using ultrasound to see inside the body. However I'm having some issues with the sender circuit, shown below:
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How to attenuate the noise in the current due to the MOSFET switching
I am making a controller to like dimmer to reduce the voltage from a microcontroller. I am using the following circuit.
However, I see that this is introducing noise into the current. I need help to ...
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