TUSB217-Q1: About selection of TUSB217-Q1 BOOST level and cable length

zehao chen

Part Number: TUSB217-Q1

Hi,

The following is the description of cable length and boost level in the TUSB217-Q1 datasheet:

In our application, there are two kinds of Pre-channel cable length:pre=0.9 meters and pre=4 meters, post=0~2 meters.
But we can not do two different hardware to meet customer's requirements,So can we set BOOST=level 2 and RX_SEN=high to meet the
application of Pre=0.9~4 meters? Does TUSB217-Q1 work steadily for a long time after this solution?

Thanks for your answer!

over 6 years ago

0 Brian Zhou over 6 years ago

TI__Guru*** 146515 points

level two is for longer cable, it can not work with 0.9m. you may try level 1 and RX_SEN medium

0 Brian Zhou over 6 years ago in reply to Brian Zhou

TI__Guru*** 146515 points

any update?

0 zehao chen over 6 years ago in reply to Brian Zhou

Intellectual 300 points

Thank you for your reply.
It's a little troublesome,Because level 1 can't meet the requirement of 4m cable, Eye diagram can't pass.
But we can not do two different hardware to meet customer's requirements,What will happen if level 2 is used with 0.9m cable?
Level 2 is used with 0.9m cable,We have done preliminary test and no abnormality has been found at present.
Thanks for your answer!

0 Malik Barton57 over 6 years ago in reply to zehao chen

TI__Guru 64326 points

Hi,

In some application over equalization when there is low loss, (0.9m case) can cause TUSB217-Q1 to over-equalize the signal. This may also cause a eye mask violation. It seems that in you test Level 2 boosting with a 0.9m cable does not cause this condition, is this correct? Could you please provide the measured eye diagrams?

0 zehao chen over 6 years ago in reply to Malik Barton57

Intellectual 300 points

Thank you for your reply.
Eye diagrams with 0.9m cables have not been tested yet.
When we have the eye diagrams results, we will provide them to you to help us evaluate the feasibility.
Thank you!

0 Malik Barton57 over 6 years ago in reply to zehao chen

TI__Guru 64326 points

Hi,

I will await your reply. In the meantime I will mark this thread as TI thinks resolved. Please reply to this thread to re-open the issues and provide additional eyes.

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TUSB217-Q1: About selection of TUSB217-Q1 BOOST level and cable length