Trying to make a brushless dc motor controller with mosfets and arduino

Other Hardware Motors, Mechanics, Power and CNC
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I am trying to control a brushless dc motor- I have a h-bridge style mosfet circuit and am controlling the gates with an arduino. However I am trying to power the motor with a 7.4V lipo battery (which is required by that motor) - the mosfets are also high current rated so shouldnt be an issue (linked here https://4donline.ihs.com/images/VipMasterIC/IC/ONSM/ONSM-S-A0003584711/ONSM-S-A0003584470-1.pdf?hkey=6D3A4C79FDBF58556ACFDE234799DDF0 ). But when I connected the battery to the circuit it all started smoking- is there something obvious I'm missing- I hadnt started the arduino program yet so none of the mosfets should've been 'open' so no current should've been drawn. I am aware that a breadboard and breadboard wires probably arent suitable for the current levels but seeing as the motor wasnt connected at this point (was just trying to test the mosfet circuit) I don't see how that could've been the issue. On that note does anyone have any advice on how to test a higher current circuit like this if breadboards don't take that much current.

motor: https://www.amazon.co.uk/dp/B075731ZJM?psc=1&ref=ppx_yo2ov_dt_b_product_details
lipo battery: https://www.amazon.co.uk/dp/B08JCM7HBH?psc=1&ref=ppx_yo2ov_dt_b_product_details
The numbers in the picture are connected to arduino pins

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I don't see any gate drive circuit in your diagram.
Those are not logic level mosfets, so not suitable to direcly drive the gates of the lower (GND) mosfets with a 5volt Arduino pin. They need 10-volt logic. The gates of the high-side mosfets must be driven with "battery voltage + 10volt". And then there is firing order, and shoot-through.
Not a beginner's task. Good luck.
Leo..

1 Like
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I see- on the datasheet the gate threshold voltage was labelled as 2-4V. A
m I just looking at the wrong thing here then?

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That's the threshold voltage, or the point where the mosfet turns off (or barely starts conducting).
Rds(on), which is he next line in the datasheet, is specified at a Vgs of 10volt.
Leo..

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Then you connected some of the MOSFETs in the wrong way.

For a first test add a resistor (~10k) between gate and source of each MOSFET and verify that then they all are off.

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