BQ25882: USB negotiation.

Kengo.Y

Part Number: BQ25882

Hi team.

Could you tell me about the USB negotiation?
My customer's circuit doesn't start charging as below.
It seems that it is negotiating many times.

VBUS(Yellow) : 5V/div
CHG_PG(Green) : 2V/div
D+(Blue) : 2V/div
D-(Pink) : 2V/div

I have a few questions about this move.

1. What's wrong with the circuit that causes this behavior?

2. Does it recognize BC1.2 connection first?

3. Are the following flows checked in order?
　How long does it take to recognize?

5. When the connection is lost, CHG_PG first? Or is USB negotiation first?

Sincerely.
Kengo.

over 5 years ago

0 Michael Emanuel35 over 5 years ago

TI__Mastermind 40755 points

Dear Kengo,

Can you please provide a schematic and/or a register dump to further diagnose this issue? In addition, can you provide waveforms of VBUS, SW, VBAT, and IBAT when this phenomenon is happening?

Thanks,

Mike Emanuel

0 Kengo.Y over 5 years ago in reply to Michael Emanuel35

Guru 11255 points

Hi Mike.

Thank you for your reply.

Other input sources will drive without this problems.
If communication is unstable, will this happen?

Sincerely.
Kengo.

0 Michael Emanuel35 over 5 years ago in reply to Kengo.Y

TI__Mastermind 40755 points

Dear Kengo,

It is very hard to diagnose this without more information. Are you able to provide a schematic, some waveforms, and a register dump in correct and incorrect operation?

Thanks,

Mike Emanuel

0 Kengo.Y over 5 years ago in reply to Michael Emanuel35

Guru 11255 points

Hi Mike.

Thank you for your support.
Can I talk in private message?

Sincerely.
Kengo.

0 Michael Emanuel35 over 5 years ago in reply to Kengo.Y

TI__Mastermind 40755 points

Kengo,

That works.

Thanks,

Mike Emanuel

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BQ25882: USB negotiation.