MosFET Module for 0-3.3v PWM

Hi all!

I have an old massage chair and fitted a Flight Controller to it. Now i want to let the chair vibrate when i push the throttle of the joystick, via Windows HID. The controller i chose is a Wemos D1 Mini. I wrote a Sketch that accepts UDP-Pakets with Values from 0-255. Those are translated to PWM Signals on the Wemos Pins. The chair operates at 12V, it's Power Supply has a 1,5A max. So, the 3 vibrating elements will take anything from 0-12V an rumble nicely. Now i need to use the PWM Signal ( ranging from 0-3.3V) to supply those 0-12V to the elements. I tried these ( https://www.amazon.de/gp/product/B07TWLLTRT/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1) mosfet modules but learned they are not suited for 3.3V PWM or even 5V since the have the least impedance only when receiving 10V. Can someone please suggest a ready-to-order replacement product or other MosFET to replace/solder on these Boards?!?

If you do a search for "logic level mosfet 3.3V" you will see many candidates. Make sure to look at the data sheets to confirm that Rds(on) is specified at lower than 5V and at the graphs to see if your required drain current is possible with 3.3V gate to source voltage.

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You need a MOSFET with low gate threshold voltage (logic-level MOSFET). Usually such MOSFETs have the letter L in its name (IRLP3034, IRLZ44N, IRL2203N, and many others) .
Unfortunately, I don't know a ready-made module with logic-level MOSFET.
You can take the module you specified above and replace the transistor in it with logic-level MOSFET.

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Thank you for your replies. That confirms what I read in another thread. I will try to get a replacement and post here afterwards. Though i am a bit surprised that there are no readymade shields with fitting Mosfets... considering that every tinkerboard I know has either 3.3 or 5 Volts for Digital Out Pins and PWM.

Try these....many others also available.
FYI........Google usually works.

https://www.ebay.com.au/itm/303879739565?hash=item46c0a4d8ad:g:S~UAAOSwgvdgIwYp&frcectupt=true

Replies #2 and 3# both answer my question, though answer #5 seems to be the most practical, because the modules suggested add an optoisolator to the game which will remove the problem of the low logic voltage, thus only the frequency affects the mosfet throughput, not the voltage. Using Mosfets like IRLZ44N will work better than the IRF520 on the modules i bought, but still result in a max. Voltage less than 12V and more heat, afai read. So, i give the D4184-Modules a try and will report back :slight_smile:

These are in the mail now:

Feedback on the D4184 Modules: They work as expected - i can regulate the source voltage of 12 V from 0 to ~11 V via the Wemos D1 mini with PWM. The logic is inverted now, but i changed that in the code. However, the chair is not yet working as intended. I have two separate circuits now, one for the Wemos, one for the rumblepacks in the chair. When i measure the voltage without a load, all is fine. As soon as i connect one rumble pack, the LED on the module lights up (same when i turn it OFF with PWM ) and the voltage drops to zero - no rumble at all. If i connect the 12V directly, it rumbles along nicely. I replaced the rumblepacks with an RC-Motor from a Helicopter - same result. I described that in a new thread...: D4184 Voltage drops to zero

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