Lebowski wrote:The controller IC basically runs a PLL, which in practise does what you say:"able internally to generate a sinusoidal frequency that is synchronized with the pulses from the Halls".

The PLL is basically a filter for the hall info. It smoothes out the hall steps. Looking at the in and output signals it performs this interpolation you mention.

If you look at the phase info, at extremely low speed you will see a staircase with 6 steps (as the motor slowly rotates and triggers new hall combos). As the speed goes

up the steps will more and more become a smooth ramp.

The controller IC does not (ever) drive the motor with a squarewave. Lets say the hall steps are at 20, 80, etc (each time plus 60) degrees.

When the hall combo says 20 degrees, phase A is driven with Amplitude*sin(20), phase B with Amplitude*sin(140), phase C with Amplitude*sin(260). So a 120 degree

shift for each phase. Since in this example sin(20) is 0.34, phase A is driven with 34% of Amplitude. At extremely slow speed the output signals will go in 6 steps through a

sine wave. And it always drives all 3 phases, not like a China controller where only 2 out of 3 are driven.

I think I understand correctly. The first CYCLE is a square cycle then after that the controller starts its RPM tracking so it can gradually change from Square waves to sine waves... Right?