TPS2546: TPS2546 charge issue in S3 status

Hi Kai,

These tests were taken with the iPhone 12 with 97% battery with a usb a to lightening cable. I did not see any failure to charge. I saw around 0.7A. The current draw is always dependent on the sink device and due to the phone having an almost full battery it did not pull max current. 

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I am wondering if your customer is having a power supply issue with the current draw. VBUS starts to ramp down before it shuts off. Can you provide a bit more voltage or increase the power supply current limit to see if that fixes the issue?

Thanks,

Emma

Thanks,

Emma

From Kai

- Regarding the power supply ability & test result, I will let customer feedback to us later.

But could you help to check if Data lines disconnected would be the root cause of this issue?

In another word, we found TPS2546 seems can’t charge normally when the setting with Data lines disconnected, Do you think this is the reason why fail to charge?

Since customer is connect a data + power cable (Apple Type-C to lightning Cable) when he testing.

I do not think that this is an issue because I emulated the customer's exact test case on the EVM, with the data lines disconnected in DCP mode and saw proper charging, per photos above. 

Let me know when you hear back on the power supply. 

Thanks,

Emma

Emma Hoying said:

om K

Hi Emma, 

Customer designed 5V/1.5A at this charge port, they had been test 5V with charge above 3A before, which is mean the DC source absolutely have the ability to support 1.5A charging. And we observe that when the fail charge status, Fault pin will not trigger (FAULT# : asserted during overtemperature or current limit conditions), so it should not be a current limit issue here.

We found only APPLE type-C to Lighting cable can duplicate this issue, and it need to connect charge port directly, if you connect a test tool like your capture, it can't duplicate the issue.

Customer is doubt that whether APPLE type-C to Lighting cable(should have a IC inside) & TPS2546 have compatibility issues, since if customer use non-apple type-C to lighting cable, it can be charge normally without any issue.

Kai

Hi Kai,

Have you tried multiple cables?

Thanks,

Emma

Hi Emma,

Yes, customer had tried three different APPLE type-C to lighting cables, no any change, all of them are failure scenario.

Kai

Hi Kai,

Can you email a schematic of the system?

Thanks,

Emma

Hi Emma,

Sure!

Kai

Hi Kai,

I received your schematic. I will follow up with you on Monday.

Thanks,

Emma

Hi Emma,

Got it, I will let customer know, and then feedback to you, thanks for your support! 

Kai