Simple MOSFET Circuits You Can Build

This video will describe how to build three simple MOSFET circuits to get familiar with their characteristics and understand how they work.

MOSFET Bootstrapping:

[calabrese]

Wow! Not only I understood everything you've explained but you've actually presented very practical circuits that can be used in real life projects. I'll borrow from you the alternating flashing lights for an emergency sign I want to build. But the most important thing is what I have learned today. Thanks man!

[shvideo]

What a great video with schematics, part numbers, and explanations. Thank you very very much. This is fun stuff!!!

Thanks. I really liked the 1st circuit that illustrates the gate capacitance of the MOSFET.
Please keep this series going.

[bernym]

Great demonstration of the capacitor effect of these devices. Thank you.

[phils]

Thank you. Very clear and and nicely presented.
I've just received some MOSFETs with an aim to do motor speed control and your simple examples help a lot. The gate capacitance seems to be the key to correct operation.
Also nice to see and hear a presentation without the music that spoils so many instructional videos.

[alphahr]

The best explanation I've seen so far, thanks

[Braz]

Your videos are very informative. I would enjoy seeing a tour of your shop/bench.

[gracc]

Awesome. You explained it so well that I actually understood and thought it was simple. Well done Sir.

[giannislymperopoylos]

ive done the capacitive switch and i have changed a few mosfets when they failed....burn out..i dont have any other experience or used irf540n which is almost identical to the irf44n and worked great at 12v as capaicitve switch ..couldnt get it worked with a 18650 fully charged at 4.2v...though i ve seen it happened....the gate threshold v for the gate is around 5v...anyway...i wanna ask
when you use the mosfet as a switch in the classic way not the capacitive one...do you need a gate driver...i mean a logic gate a chip a microcontroller ..sorry for my terms ....dont know ...that can give the signal voltage to the gate...in order to make it work...
im askin this...i have a 12v load i wanna switch...i have a 12v source....i connect the positive to the gate of the mosfet and then through a resistor to the then to the ground...i connect the load on the drain positive side of load ..negative side of load ...drain...if i have a switch a typical switch on the voltage i feed the gate...will it work...?willl i be able to switch the mosfet on and off and control the load?

[arindambala]

This is really a great video... Thank you so much Sir.

[HunterStilp]

Are the power rails on the breadboard connected in reverse?

[holliedog]

Great video, thanks can you tell me how to make a simply adjustable timer to operate a relay for a max time of 1 second, thanks

[waterfuel]

How do I allow higher volts on output to load using N channel MOSFET, zener, resistor, as zener resistor is to be called minimum load, on all the time while final load turns on and off by it's own switch in series, while MOSFET is always on also.100% duty cycle minimum load, and 40% duty for final load resistance? Vcc 28v DC or higher, 6 A final load, MOSFET type for higher gate voltage? This for series pass transistor needing 28VDC on load. The BIPOLAR type lose voltage on load with Zener. ( In other words if minimum and final resistance is together in parallel, the ohms goes down and is wrong.)

[albertanasoul]

Thank you for the video, it is well explained. I am new to electronics, so easily confused. In the touch switch you created, I have seen it done with a Z44 and he didn’t even use a resistor. I understand what a resistor does, but why is it necessary here? Also is it possible to make a dimmer touch switch for 12V supply?

[randojoe]

For the first design, how do you make the touch sensors? Are they simply non-insulated wires?

[spiderjuice]

Great video!
Not sure if you're still checking comments, but I have a question. I get that MOSFETs are great for switching DC, but what about AC? Must I use a relay, or is there something analogous to a MOSFET which would allow me to switch AC on and off like this (either an AC or DC trigger would be OK)? I can only think of a relay right now, but I'm no expert.

[petersack]

hi thankyou.. i dont have any of those irf 1405 MOSFETS. i got k8a60da n channel ; 65r6000 n channel: rfp40n10 ; irf640; ]
would these work ?// ???

[incxxxx]

Does the mosfet in the curcuit with Schmitt trigger should be special otherwise the LED does not blink?
I used FQPF mosfet. The LED does not blink. No oscillation on the gate.

[monh]

The pulldown resistor value . how to choose the right value?

[UpcycleElectronics]

So.... there's this guy on YouTube... he showed an alternating flasher circuit that was much more simple and used fewer parts. You can look it up. I think he named the video 1970's GM blinker circuit...or something like that

;-p
-Jake