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Mosfet Transistor N-channel Getting Hot, What Should I Do?

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If you want to use OpAmps and eliminate shoot through currents, use the window comparator technique:
https://www.electro-tech-online.com/custompdfs/2010/02/cd_230060.pdf
An RC circuit on Vin could be added if the OpAmps are very slow driving the gate capacitance of the FETs. Note that this circuit requires both P and N channel FETs to work.
 
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Young man:

1st. We are not saying anything wrong.
2nd. To use an ammeter, you use it in SERIES, not in PARALLEL.
3rd. Direction DOES matter. Current flows from DRAIN to SOURCE. If you wire it wrong way = SHORT CIRCUIT, because you forward bias the FET's internal protection diode.

Yeah that's why I'm asking, as I simply don't know and if I don't know I ask. Sorry if I offended you Hayato, never said you guys were wrong, I was stating whatever you all were referring to as being wrong I tried to correct.
 
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I'm not offended.

Well, tell me the functions of every mosfet over there. Why Q1, Q2, Q3 and Q4 are there. Maybe I can understand better what are you trying to do.
 
For example. Q1 and Q2, are reverse biased, their sources are connected to 9V.

Your motor will never spin, because you have Q4 and Q3 grounding both terminals. And Q4 and Q3 are grounding the reverse biased Q1 and Q2 as well.
 
For example. Q1 and Q2, are reverse biased, their sources are connected to 9V.

Your motor will never spin, because you have Q4 and Q3 grounding both terminals. And Q4 and Q3 are grounding the reverse biased Q1 and Q2 as well.

Well see everything is working fine, and I just tried both circuits that I've placed in this thread for you all and both are giving me the same results. I'm trying to build a Solar Tracker, and so far, everything is working fine, but when I turn up my power supply over 6-7v, either my front 2 FETs start to become extremely hot (then eventually fry) or my back 2 FETs become extremely hot, depending on which circuit diagram I'm using.

And when measuing how much current was coming out of my FETs, it was insane. Example, if my power supply is at 10v, my FET may be pushing 5A to my motor and only 500mV, and I believe my FETs can only handle up to 4A.

So I was wondering if I get this FET here at Jameco.com would I have those issues: Jameco Electronics ICs & Semiconductors: INTERNATIONAL RECTIFIER: IRFZ44NPBF

It can handle way more current (I) than my current FET. Again, everything is working fine, I'm just having that one issue.
 
The first schematic has Q1 and Q2 as source-followers. Their gates must be +17V for them to fully turn on but their gates are only +5.5V so they just barely turn on. Q3 and Q4 are upside-down and should be P-channel mosfets.

The last schematic shows Q1 and Q2 upside-down. You have the sources connected to +9V but the sources must connect to ground for these N-channel Mosfets. Q1 and Q2 should be P-channel Mosfets but then you will have the very high current "shoot-through" problem when the motor direction is changed.
 
Be sure to read the OP's other thread with the same problems, for the other half of this discussion.
It is stupid to have two threads about the same circuit.
Is is also stupid for him to post his wrong schematics on another website instead of attaching them here.
He doesn't understand that Mosfets need a gate-source voltage of 10V to fully turn on and that N-channel source-followers should not be used as high-side drivers in an H-bridge.
He also doesn't understand that adding an LED at each gate severely limits the gate voltage. The LEDs don't even have current-limiting resistors.
 
It is stupid to have two threads about the same circuit.
Is is also stupid for him to post his wrong schematics on another website instead of attaching them here.
He doesn't understand that Mosfets need a gate-source voltage of 10V to fully turn on and that N-channel source-followers should not be used as high-side drivers in an H-bridge.
He also doesn't understand that adding an LED at each gate severely limits the gate voltage. The LEDs don't even have current-limiting resistors.

On the other thread, I was focused only on the schematic of building a Solar Tracker, and in this thread I was focused only on why the FETs were becoming hot. Yeah, I mentioned the solar tracker here, but that wasn't the main topic of this thread, thus why I opened another one. I was sure others here have built a Solar Tracker, so if the thread title displays a question regarding a solar tracker, there is a huge chance they will give their advice. This thread on the other hand from the thread title would make one think it's only about FETs. So audioguru or anyone else can call it what they want for all I care, but that was my reason. :)

There is a lot I do not understand as well as many other new comers here at this forum, but it's hard to see how such a respected member here receives high respect for bashing other new members for things they may or may not know. Honestly audioguru, if it bothers you so much, just do me and others a favor and focus your attention and support on other threads. Or better yet, why not send me a kind PM here at the forum explaining what I could have done next time instead (Ex. "Kindly letting me know I can attach files here instead of having to upload them to another source").

Anyway, no time to focus my energy on negative comments, so back to my project...
 
I recall that I made some suggestions to drive the transistor in the other thread. Have you tried those suggestions? It's probably a good idea to step back and study some examples of a working MOSFET H-drive. It's way past my bedtime so if you haven't found one by tomorrow afternoon I'll see then what I can do. Look on the net for "high side driver".
 
I recall that I made some suggestions to drive the transistor in the other thread. Have you tried those suggestions? It's probably a good idea to step back and study some examples of a working MOSFET H-drive. It's way past my bedtime so if you haven't found one by tomorrow afternoon I'll see then what I can do. Look on the net for "high side driver".

Yeah I haven't had a chance to yet as I'm trying to get a broad idea of all the suggestions first before I decide which route to go, as some methods require adding a component here and there to fix it, some suggest using a whole different design, so I haven't made it that far yet as to which method to take yet. Thanks for your help so far though :) Will keep you posted
 
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