Part Number:DRV10974
I'm looking into sensorless, brushless DC motor drivers with integrated drive FETs. I've been testing with the eval boards for the DRV11873, DRV10974, and DRV10975, trying to drive 3 similar motors.
The DRV11873 has the least options for tuning, but it works great for all 3 motors. Motor startup is fast and consistent. The DRV11873 uses trapezoidal drive as opposed to sinusoidal drive like the other two drivers.
For the DRV10974, there are several resistor options for tuning. I've gone through the tuning procedure document and also a lot of trial and error. Even after that, none of the 3 motors will consistently start up. About 1 in 30 times the motors will fail to transition from the open loop to closed loop control on startup. The DRV11873 doesn't have the same, slow (1 to 2 seconds) startup ramping that the DRV10974 does.
Besides sinusoidal drive, I'm wondering what the differences are that might be giving us trouble. Why do the DRV10974 and DRV10975 need to be fine tuned for a specific motor, vs. the DRV11873 which seems to just work fine without tuning. What advantages are there with the DRV10974 vs. the DRV11873? How much more efficient can we expect sinusoidal drive to be for a ~4W motor?