Driving a Y-configuration brushless DC motor [solved]

My latest project involves getting a BLDC motor from a hard drive spinning at an appreciable rate. My original approach was to leave all of the hard drive tidbits connected and just apply power to the hard drive's power pins, however after a minute or two the drive spins down in what I can only imagine to be the HD controller panicking because its read/write arm has been disconnected.

So the next step was to figure out how to drive it myself. After a few hours googling reading whitepapers from Atmel/Microchip/whoever on driving BLDC motors, I came to the conclusion that building my own driver was outside my technical expertise.

After a bit more googling, I discovered a handful of purpose-made ICs for driving BLDC motors like this one. Now the problem was actually sourcing one of these driver chips. It seems like every supplier is either some sketch chinese site or requires all orders to be in multiples of 1000.

tldr: how the hell do people actually drive these motors?

The easy solution is to use a rc ESC like this


A r/c ESC are controlled like a servo, so you can control the speed by using the Arduino servo lib

The maximum speed of the motor will depend on the supply voltage. Motors designed to run at 3600 rpm from a12V supply probably won't go much above 5000 rpm flat out from 12V, depending on how much overhead was allowed in the design.

There's an Open BLDC driver project somewhere BTW.

You know I actually just spent half an hour going through this forum’s history and found this gem:

Easy to use and set up and not foreign sourced. It’s amazing that this post didn’t show up on google.

If I can’t get this driver chip to work, I’ll give the ESC suggestion a shot. Thanks for the replies.