Part Number:DRV8308
Dear Sirs,
Waiting for an reply, I start another thread.
We think that the driver does not work as the manual says.
After several tests we have concluded that:
Neither SPEED nor LOOPGAIN are gains applied to the error signal to calculate the output. If we cancel the integral factor, by doing zero SPDGAIN, and keeping SPEED and LOOPGAIN, the motor speed in the acceleration and steady state are always the same regardless of the setpoint.
Even the constant speed may be greater than the setpoint, which makes no sense in a proportional regulator.
In our opinion, SPEED and LOOPGAIN are not gains but constants added to the output. Without integral factor they are directly the output.
Another thing, LOCKn does not signal the transition from the proportional interval to the integral interval.
Are we wrong?
Thank and best regards