I would like to power my Arduino and BLDC to be powered with an old computer power supply. My Arduino needs 5V and my 3 phase BLDC needs 12V.
- I'm using a SLA5068 N-channel MOSTFET bridge. Datasheet Here.
- My sequence is taken from the library AccelStepper--here is the homepage. The sequence has 3 steps; during each step, only one phase will be on.
- The BLDC motor I'm using is one from an old Western Digital 500gb HDD. I can't find the specs for it, but I know it's rated for 12V because I looked up a datasheet for the motor controller chip that was on the board with it.
- If I use the 5V for powering my BLDC, it works just fine (except I can't go very fast).
- If I use the 12V supply, it works for a moment and then shuts off.
Things I've tried
- Putting a 1K resistor from the 12V to ground. Also tried with a 570 ohm
- Putting in a capacitor to ground.
- Putting a fan from the 5V to ground so it has a constant load.
- Putting a flyback diode in the circuit.
The most puzzling thing
This works fine with my computer fan, which is a BLDC that has a controller circuit built inside it; this leads me to believe I am missing something in my design.
Perhaps this is an important detail, when I use the 5V supply for my 3 phase BLDC, I don't hear any clicking, but when I use the 12V supply, I hear a lot of clicking and then it shuts down quite promptly.