Original question:
Hi
We see an issue that when charging iphone 6S, the iphone 6S touch response will delay. Would you help review if below DP and DM behavior are correct ?
Below are the waveform (Purple line is DM waveform, the Blue line is DP waveform)
1. Waveform before connected to iphone 6S (DP is 2.84V、DM is 2.17V)
2. at the moment iphone connected, see DP and DM drop as below wave form.
Then DP DM become this waveform
finally it will settle at below waveform (within 20 sec after the iphone are plugged)
Hi Emma,
I labeled the voltage as below
1. Waveform before connected to iphone 6S (DP is 2.84V、DM is 2.17V)
2. at the moment iphone connected, see DP and DM drop as below wave form.
Then DP DM become this waveform
finally it will settle at below waveform (within 20 sec after the iphone are plugged)
Hello,
Thank you for your clarification. The scope captures show the DP and DM lines going through enumeration in order to settle into the correct DCP charging scheme. This is the DP DM pin's expected behavior. Below is more explanation from the datasheet about the different charging modes DCP auto offers.
Thanks,
Emma
