Hard drive spindle motor? - FrontMotion Firefox. Circuits - FrontMotion Firefox.
W1ngs' Electronics - Schematic and Description - FrontMotion Firefox. Moving on from the introduction, I present the schematic and description for my current hard drive motor controller setup. Click for Full Version Above is the complete schematic for my controller. I'll explain the circuit in sections so it's easier to understand. To begin with, let me start at the beginning with the motor's position sensors and the comparators which turn their small sine waves into proper square waves.
What you see below are the sensors, labeled A, B, and C; these are hall effect bridges as seen on most brushless DC motors which include internal sensors. FQQ9SQZFQR1H6EW.pdf (application/pdf Object) - FrontMotion Firefox.