SLLU336A May   2021  – January 2022 MCT8316A

 

  1.   1
  2.   2
  3.   3
    1.     4
      1.      5
      2.      6
      3.      7
        1.       8
        2.       9
        3.       10
  4.   11
    1.     12
    2.     13
      1.      14
    3.     15
      1.      16
    4.     17
      1.      18
    5.     19
    6.     20
      1.      21
      2.      22
      3.      23
      4.      24
  5.   25
    1.     26
      1.      27
      2.      28
      3.      29
    2.     30
      1.      31
      2.      32
    3.     33
      1.      34
      2.      35
      3.      36
      4.      37
      5.      38
      6.      39
      7.      40
      8.      41
      9.      42
      10.      43
      11.      44
      12.      45
      13.      46

4.3.1 Initial speed detection of the motor for reliable motor resynchronization

The Initial Speed Detection (ISD) function is used to identify the initial condition of the motor. It is important to know the initial condition of the motor for reliable resynchronization. Motor resynchronization failures can occur when the device attempts to start the motor while the motor is coasting or spinning in the direction opposite to the intended direction of spin. Motors can coast in applications that require frequent motor starts and stops, or if the motor Is being forced externally or if there is a power interruption. Motors can spin in the direction opposite to the intended direction of spin if motor phase wires are connected to OUTA, OUTB and OUTC in wrong sequence or when wrong direction command is issued. Motors with higher inertia coast for a longer period of time. It is recommended to have ISD enabled in applications that require frequent motor starts and stops and use higher inertia motors.

Step 1: Enable ISD [ISD_EN]

Step 2: Enable Motor ISD Resynchronize [RESYNC_EN]

Note:

If the motor fails to startup, increase the Motor Stationary BEMF Threshold [STAT_DETECT_THR].