TUSB211-Q1: Connection b/w D1x and D2x

Ryuuichi machida

Guru 11515 points

Part Number: TUSB211-Q1
Other Parts Discussed in Thread: TUSB211

Hi,

I would like you to confirm about below.

* According to datasheet of TUSB211-Q1, there is following description.

"D1P must be shorted to D2P" and "D1N must be shorted to D2N"

However, if user do not short D1P and D2P, D1N and D2N, what kind of problem will be observed ?

I guess one of the problem is when USB datastream is available b/w host and device, if TUSB211 enter power down(this means RSTN is enabled or Vcc is disconnected), USB datastream will be not available as well.

If D1P and D2P, D1N and D2N are shorted, in above case, function of TUSB211 are not enabled, but USB datastream continue to be available.

Is my understanding correct ?

Best Regards,

Machida

over 6 years ago

0 Cevin over 6 years ago

TI__Intellectual 1165 points

Hi ,

D1P must be shorted to D2P and D1M must be shorted to D2M to ensure correct functionality (availability and signal conditioning of USB datastream) of TUSB211 independent of enable status.

Best regards

Cevin

0 Ryuuichi machida over 6 years ago in reply to Cevin

Guru 11515 points

Hi Cevin-san,

Thank you for your reply.
If user do not use High speed mode, should this requirement(short to D1P and D2P, D1N and D2N) be met ?
According to your reply, It seems that purpose of short of dataline is for signal integrity. So if user will use Full speed or Low speed, this requirement may not be met..

Best Regards,
Machida

0 Cevin over 6 years ago in reply to Ryuuichi machida

TI__Intellectual 1165 points

Hi Machida-san,

This requirement has to be always met, regardless of High/Full/Low-Speed as the pins are not internally connected inside TUSB211. Please see page 12 of datasheet for recommend landing pattern with the DP and DM traces routed underneath the device.

Best regards
Cevin

0 Ryuuichi machida over 6 years ago in reply to Cevin

Guru 11515 points

Hi Cevin-san,

Thank you for your reply.

I understood.

BR,

Machida

Interface

Interface forum

TUSB211-Q1: Connection b/w D1x and D2x