60
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How to design the gate resistor value?
Understanding The Gate Of A MOSFET
MOSFETs are remarkable devices which provide many benefits when driving various loads. The fact that they are voltage driven and that, when on, they have very low ...
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20
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How to design the gate resistor value?
If you selected this driver, which has huge output current (7A) then I presume you need this gate drive current to switch a very large FET very fast.
The gate resistor will only slow things down by ...
- 60.1k
18
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Bootstrap circuit for high-side MOSFET driver
simulate this circuit – Schematic created using CircuitLab
Note 1: The input voltages are only \$V_{cc}\$ and \$V_\text{High Voltage}\$. You don't apply anything at the \$V_{BS}\$ node. It is ...
- 13.5k
17
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Driving highly inductive loads destroys mosfet driver
Holy Carp! You're trying to do 10's of nsec switching on a solderless breadboard? And you don't have a flyback diode on your transformer?
If you're going to do this stuff, you've got to learn to ...
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17
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Proper way of connecting logic GND / power GND on MOSFET driver
I've answered a question very similar to this here (How do I design correctly ground plane separation for Texas Instruments TPS63060 IC?), but I'll tweak a reply for you here.
IRF is asking you to ...
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17
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p-channel MOSFET switch
First off, the rules of the site do state not to ask for recommendations of products, so I will skip that bit. Just read the datasheets as everything will be explained in there. If there is something ...
- 11.5k
17
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Is paralleling MOSFETs a good or a bad idea?
I see no problem with it. It is also best for them to share the same heat sink and be switched at a reasonable speed and proper gate voltage. If one starts conduction more than the others it will get ...
- 2,994
17
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Why can't an MCU's GPIO pins directly control power MOSFETs?
Sometimes they can. But when they can't there are two main reasons- not enough voltage and/or not enough current.
The voltage is required to get many MOSFETs to turn on so they have low resistance. ...
- 332k
16
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Is paralleling MOSFETs a good or a bad idea?
It is perfectly fine and frequently done.
Even if the devices didn't turn on (or off) simultaneously, the (possibly) higher current for a brief time won't cause any damage.
Note that it is better to ...
- 13.9k
15
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Why doesn't shoot-through occur on totem-pole structure?
These transistors don't conduct unless Vbe>0.6V for the NPN, Vbe<-0.6V for the PNP. And as the bases and emitters are tied together, it is impossible for both these conditions to be true at the ...
- 66k
15
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Why do I keep burning my mosfet?
Lose the diode. I can't even guess what you think it does, but it will prevent the FET from being turned off quickly.
The FET driver will drive the gate high quickly, which turns on the motor. ...
- 306k
15
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p-channel MOSFET switch
The trouble with using a high side P channel MOSFET driven from a signal that doesn't get close (less than 0.5 volts) to the high side voltage is that there is a decent probability that it will appear ...
- 385k
14
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Accepted
Designing a *linear* MOSFET driver stage
This is indeed an interesting problem, because of the variation of effective load capacitance with the load resistance due to Mr. Miller, and your need to not overcompensate it.
I suspect a biased ...
- 332k
14
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Is it better to use a MOSFET with a gate driver IC or a MOSFET with a lower VGS,on?
which is best for fast switching do I need to use MOSFET driver IC such as ICL766 with IRFZ44n or is it better to use lower VGS MOSFET such as AO3400
You don't want fast switching to drive LED strips!...
- 60.1k
14
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Is paralleling MOSFETs a good or a bad idea?
The PTC characteristics of most FETs make this a valid application for digital or fast dVgs/dt switching, but not slow switching in the linear high power region as commonly ignored due to parallel ...
- 137k
13
votes
Resistors getting hot in this MOSFET driver circuit
Here is your circuit being discussed:
R3 and R5 should not be getting "hot".
Do the math. Even if Q1 were a perfect switch, there would only be 5 V across R3. (5 V)2(1 kΩ) = 25 mW. Unless ...
- 306k
12
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Why doesn't shoot-through occur on totem-pole structure?
In a true totem pole configuration, shoot thru usually does occur for a very short time during switching.
However, what you have is not a totem pole configuration. You have two emitter followers ...
- 306k
12
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Resistors getting hot in this MOSFET driver circuit
Figure 1. When Q1 is off both Q2 and Q3 are forward biased (green) and will turn on. The result will be shoot-through the two transistors (red).
If the supply voltage doesn't collapse (1) will be at ...
- 160k
12
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Can you drive a P-MOSFET as a high side switch directly from a microcontroller?
If I use a GPIO configured as open drain output, not push-pull, and
use a pullup resistor between the gate and source of the P-MOSFET
and
It this OK to do so ? Am I correct, or am I missing ...
- 385k
11
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p-channel MOSFET switch
Here is another approach that uses an N-MOSFET in a level shifter configuration that does not invert the control signal polarity.
simulate this circuit – Schematic created using CircuitLab
You ...
- 45.7k
10
votes
Designing a *linear* MOSFET driver stage
Outcome Report
Okay, the short story is: adding a discrete buffer worked! That said, I don't think I'll design my circuit this way, rather I'll go with the recommendation of @Spehro and @...
- 6,842
10
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Power MOSFET gets hot while driving Peltier by step-down buck voltage converter
To protect against possible future edits, here is the circuit we're talking about:
Major problem are:
There are no component designators in the schematic, making the circuit hard to talk about.
The ...
- 306k
10
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Accepted
Why does my MIC4605 keep blowing up?
On your layout the decoupling cap (finger-painted red) is very far away from the chip, there is a 5R resistor in series (purple) and the current loop area (highlighted in yellow) is quite large.
This ...
- 60.1k
10
votes
MOSFETs on Motor Controller died
They got destroyed due to inductive kickback. The TVS diode is not a correct choice, you should use a schottky diode at that position.
When the MOSFETs were switched off, the motor induced a high ...
- 23k
10
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Accepted
Can I drive a low-voltage MOSFET gate directly from a microcontroller?
The answer is yes, and no. I mean it depends on what you need to do with the load.
For simple and relatively slow on/off switching you can do it provided that…
Your MCU has sufficient output level: ...
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10
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Why can't an MCU's GPIO pins directly control power MOSFETs?
The MOSFET gate turn-on voltage may be higher than what an MCU I/O pin can provide. A driver circuit can translate the I/O logic output voltage into a strong 'on' gate voltage.
A MOSFET drive circuit ...
- 17.9k
9
votes
Driving highly inductive loads destroys mosfet driver
A combination of the IRF840's reverse transfer capacitance (120pF), the dv/dt of the drain voltage and the rather weak driver (MCP1402) is my best guess.
Starters, read the data sheet on the driver - ...
- 385k
9
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Drive a MOSFET via BJT?
This is called "push pull output configuration" and provides unity voltage gain but significantly low output impedance and high output current. This makes push/pull output ideal for driving high ...
- 17.7k
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