TPS25830A-Q1: When TPS25830A-Q1 was operating in device mode, the DP/DM out eye diagram performance will be worse than operating in host mode.

Roy Chou1

Part Number: TPS25830A-Q1

Hi team,

We find that the eye diagram performance is worse when we set TPS25830A-Q1 in device mode. But as I know, both of host mode and device mode should pass through the internal MOSFETs. The only difference is buck converter whether is under operating.

Can you let me know the result is normal or not? Thanks.

Roy

over 3 years ago

0 Roy Chou1 over 3 years ago

TI__Genius 16090 points

Hi team,

We found that the root cause is that buck converter is working or not. If we issue the command to disable the Vbus, and then we can see the eye diagram will be worse.

Roy

0 Bob Ma over 3 years ago in reply to Roy Chou1

TI__Expert 8980 points

Hi, Roy,

Thanks for reaching out. I am assigning this to Jianhua and we will discuss this and reply you tomorrow.

Regards,

Bob

0 Jianhua Liu over 3 years ago in reply to Roy Chou1

TI__Intellectual 1000 points

Hi Roy,

1. Do you mean it worsens the performance as in client mode? It doesn't make sense as buck disabled with worse performance.

2. Have you added the LC at DP/M_IN side?

For TI's policy, will click resolve button first.

If any, contact me any time.

Thanks.

0 Roy Chou1 over 3 years ago in reply to Jianhua Liu

TI__Genius 16090 points

Hi Jianhua,

We used CTRL to control mode.

vbus on = CDP/SDP mode

vbus off = Client mode

In client mode, the eye diagram will be worse.

Jianhua Liu said:
1. Do you mean it worsens the performance as in client mode? It doesn't make sense as buck disabled with worse performance.

Yes.

Jianhua Liu said:
2. Have you added the LC at DP/M_IN side?

Yes.

May I add you in the mail loop with customer?

Roy

0 Jianhua Liu over 3 years ago in reply to Roy Chou1

TI__Intellectual 1000 points

Hi Roy,

Sure, please loop me in the email, or forward the information to me.

And did you have any chance to check this with our EVM board?

Jianhua

Interface

Interface forum

TPS25830A-Q1: When TPS25830A-Q1 was operating in device mode, the DP/DM out eye diagram performance will be worse than operating in host mode.