MCF8329A: Motor Studio Usage issues

Tool/software:

Hi,

   I set the maximum speed of the motor to 320Hz, but the observer can only estimate the maximum speed (Speed FDBK) to 280Hz.At this time, the power supply voltage is 12V.

   However, when I increase the power supply voltage, the Speed FDBK will increase.

   Does this mean that this motor can only reach a maximum speed of 280Hz at 12V?