TPS65988: TPS65988 CC waveform when insert adaptor

John Liu59

Part Number: TPS65988
Other Parts Discussed in Thread: TPS65982DC, TPS65982,

Dear all,

My customer test the CC waveform with TPS65988DJ when insert the PD adaptor, after the VBUS voltage rise to 20V, one CC is high and one CC is low(the voltage is not zero)

But when using TPS65982DC, the waveform is different, one CC is low(0).

Could you please help advise if the waveform looks normal, why it is different for the two waveform?

Below is TPS65982 waveform:

Below is TPS65988 waveform:

Thanks.

over 6 years ago

0 Adam Mc Gaffin over 6 years ago

TI__Mastermind 30000 points

Hello John,

This is normal behavior as the TPS65988 supports VCONN while TPS65982 does not.

Hope this answers your question! If so, please click THIS RESOLVED MY ISSUE

0 John Liu59 over 6 years ago in reply to Adam Mc Gaffin

TI__Intellectual 2735 points

Hi Adam,

Could you please help explain more about the difference.
For TPS65982DC, in the datasheet I also find there is PP_cable can provide power to CC line, what do you mean TPS65982 can not support VCONN?

Thanks.

0 John Liu59 over 6 years ago in reply to John Liu59

TI__Intellectual 2735 points

Hi Adam,

Could you please give more explanation for the difference?

Thanks.

0 John Liu59 over 6 years ago in reply to John Liu59

TI__Intellectual 2735 points

Hi Adam,

Could you please help give more detail for the two difference between them?
Why one CC is different for the two parts?

Thanks.

0 John Liu59 over 6 years ago in reply to John Liu59

TI__Intellectual 2735 points

Hi Adam,

Any update for the above question?

Thanks.

0 John Liu59 over 6 years ago in reply to John Liu59

TI__Intellectual 2735 points

Hi Adam,

Could you please help give updates for above questions?
The waveform is different, we want to know why there is difference.

Thanks.

0 Adam Mc Gaffin over 6 years ago in reply to John Liu59

TI__Mastermind 30000 points

Hello John,

Apologize for the late reply I have been out traveling for business.

Re-reading my original reply, my wording was a little confusing. Both the TPS65988 and TPS65982 are capable of supplying VCONN.

However, in the example you showed above for the TPS65982, VCONN is not being supplied, while in the TPS65988 VCON is being supplied. So to answer your question, these captures are normal and expected because VCONN is supplied in one capture but not the other

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TPS65988: TPS65988 CC waveform when insert adaptor