TUSB4041I-Q1: Pull-down pin is not Ground potential.What are the possible causes?

user3668508

Part Number: TUSB4041I-Q1

Dear Team,

About TUSB4041I-Q1

The TEST pin (17pin) is pulled down with 4.7kΩ, but the potential of 17pin is about 1.2V.
8pin, 9pin, 10pin are also pulled down, but they do not fall to the ground.
What could be the cause?

We are in trouble because the IC doesn't work.
Oscillation does not start either.

Thenks

over 3 years ago

+1 Malik Barton57 over 3 years ago

TI__Guru 64326 points

Hi,

First I would check the soldering of the part on the PCB. You should try reflowing that part and making sure the ground pad has ample solder. Next you should ensure that the part is getting the appropriate power and voltage levels on the power pin.

Check the reset sequence of the hub. Refer to link below and section 7.6 Power-Up Timing Requirements for reference.

https://e2e.ti.com/support/interface-group/interface/f/interface-forum/719918/faq-how-do-i-debug-a-ti-usb-hubs-when-downstream-ports-are-non-operational?tisearch=e2e-sitesearch&keymatch=faq%25252525252525253Atrue#

0 user3668508 over 3 years ago in reply to Malik Barton57

Prodigy 180 points

Dear Malik Barton57,

Thank you for your reply.

As you told us, the cause of the problem is
The Hub-ThermalPad was not soldered properly.

Thank you very much for your support.

Interface

Interface forum

TUSB4041I-Q1: Pull-down pin is not Ground potential.What are the possible causes?