Hi. I've been looking at all the chips selected for theese designs and most of em are not good at all. The 141 chip from ST needs a center-tap to work right.
There is however a great chip from Toshiba called TB6537F. Datasheet avaiable here:
Basically, this is a fully-fledged brushless controller. It has most of what it needs buildt in.
- PWM input (wants about 16 khz) for speed controlling
- buildt in startup logic
- stops when no pwm is received (PWM = 0% duty)
- small and light (24 pin SSOP only 0.32 grams!!!)
- over-current protection
- no center-tap needed
- programmable lead angle: 0, 7.5, 15 and 30°
- 2 external opamps, 1 for OC detection and 1 for commutation wave amplification.
- 1 3-phase driver array or 6 FET's + 3 drivers for the P-FETs.
- crystal/oscillator (1-10MHz)
and a PWM signal!
I am working on getting my hands on one of theese chips. They should integrate very well with any small microchip both AVRs and PICs.
With a 10 MHz resonator max speed should be about as good as the MGM controllers.