AVR-Chat

> ... If it has only two leads, it is NOT a BLDC motor. Period.

Perhaps my confusion comes from experience.  I have PWM'd two-lead 
maglev brushless DC blowers 
(http://www.sunon.com.tw/products/pdf/2005dc-maglev.pdf), and I've PWM'd 
small brushless DC gearhead motors 
(http://www.copal-usa.com/PDFs/LB16-030-AA.pdf).  Since these contain 
integrated driver electronics, each offers only two leads; PWM'ing these 
motors' power supply to moderate speed works fine and there is no 
identifiable relationship between PWM frequency and motor speed as, I 
think, one should expect.

There are, it appears from a quick search, many more examples that are 
as you describe, open-coil motors that need a multiphase driver or 
controller to operate.  Perhaps my confusion was a matter of scale.  
Thanks for the, uh, clarification.


Tom