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DRV8305-Q1: No output on the Hi-side side at Duty 90-93%.(Fault judgment has not been made.)

Part Number: DRV8305-Q1
Other Parts Discussed in Thread: DRV8305

Symptoms occur at 90, 91, 92, and 93% when the duty ratio is increased from 80% to 1%. (Does not occur after 94%)

・ When the above four duty ratios are set, the symptom always reproduces.
However, in the process leading up to the onset of symptoms, the output follows the duty ratio setting, but suddenly does not follow.
In addition, the follow-up is restarted unexpectedly, and the operation of not following suddenly is repeated.
This symptomatism occurs only in the upper output of the pre-driver, and the lower output continues to follow normally.
The motor goes into an awkward rotating state, such as STOP & GO, in response to repeated symptoms.

・ FAULT did not occur while this symptomatology was repeated.
The output on the lower side of the pre-driver is following, and it does not match the specifications that the upper and lower stages are fixed to LOW when FAULT occurs.
It can be concluded that FAULT does not occur. Even if FAULT has occurred, the clearing procedure has not been performed on the MCU side.
Therefore, the symptom that the lower output follows does not match the FAULT specifications.

pwm 15khz/DEAD_TIME 0x7:5280ns

I want to control smoothly up to 100% duty

1. Judgment result as to whether the symptom is judged as normal or abnormal operation

2. Causes of symptoms and measures to prevent or avoid the occurrence of symptoms

3. Why logical mismatch FAULT is not detected when symptoms occur

4. Whether or not to disclose technical and specific details regarding the operation of the “state machine” built into the gate driver in the pre-driver
If it is possible to disclose it, please disclose it.

5. Whether or not to disclose technical and specific details regarding the operation of the “handshaking” built into the gate driver in the pre-driver
If it is possible to disclose it, please disclose it.

6. Disclosure of the breakdown of the dead time configured in the pre-driver and the range of the dead time shown to be within the TDRIVE time
If it is possible to disclose it, please disclose it.

7. Whether or not to disclose technical and specific details regarding the operation when “simply terminate”
If it is possible to disclose it, please disclose it.