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DRV8899-Q1: 负载开路检测 Open circuit load detection

Part Number: DRV8899-Q1


你好:

   我们在使用8899时,如果开启负载检测,在没有拔掉电机的情况或者电机没有工作的情况下 也后读到开路故障,请问如果才能正常读取到开路负载故障;即拔掉电机才能读取到开路故障。其他情况下 不能误报开路故障。谢谢。

Hello: 
When using 8899, if load detection is enabled and an open circuit fault is detected even without unplugging the motor or the motor not working, may I ask if it is necessary to read the open circuit load fault normally; Only by unplugging the motor can the open circuit fault be detected. In other cases, open circuit faults cannot be falsely reported. thank you.

  • Hi,

    We have received your post and the investigation will take some time. Thank you for your patience.

  • Hi,

    Please see below information from the datasheet. When the motor is stopped in any of the electrical angles during stepping for longer than tOL an open load will be reported even if the motor is connected properly. To avoid this potential false reporting the step input position must not be stopped at any one of these four positions. The electrical angle positions and the phase currents A and B with indexer step position is given in the datasheet in sections, Table 7-3. Relative Current and Step Directions, Table 7-4. Full Step with 100% Current and Table 7-5. Non-Circular 1/2-Stepping Current. Depending on the step mode used in the application half step or microstep modes follow the step positions vs. electrical angle. 

    There is no other way to avoid this situation. If the step position could not be tracked accurately in the MCU another approach would be to disable OL detection before stopping step pulses and re-enable OL detection after step pulses are started again. This can also avoid a false OL reporting. With this approach OL cannot be detected when the step inputs are stopped. Thank you.