Brushless DC motor of HDD with Arduino

I present a driver for hard drive disk motor based on Arduino and three discreet half H-bridges mounted on proto PCB. Power supply voltage is 12V and current consumption is around 500mA.

Rys. 1 - Theory of driving three phase motor if you use a driver with high-Z output state.

During my first attempt I used L289 chip and I achieved maximal rotary speed around 2900RPM. Using the circuit presented on Rys. 2. I reached the same speed until I was using a simple driving scheme. It means with one phase which breaks the motor. After an upgrade to the scheme from Rys. 1. the rotary speed increased to 7500RPM. Theory, hardware and software are described very well one the website http://elabz.com/.

Rys. 2 - Electric scheme of half H-bridge I used.

Arduino libraries:

BLDC motor Arduino library v0.2