DRV8306EVM: GHA abnormal behavior

Hi TI Expert,

We found the behavior of DRV8306 is different from the operation mode in the datasheet.

As you can see in the below waveform, the GHA is switching when GLA is low which is not one of the operation mode in the above table.

May I know whether it is normal or what might cause the GHA switching while GLA is low?

Looking forward to your reply.

Thank you.

Condition : 

Ch1: TP24_PWM_ duty -> 20% high、80% low

Ch2: GHA

Ch3: GLA

Ch4: BLDC_U(SHA)

DIR -> Low