TXB0104: TXB0104RUTR_issue

faith_bill

Prodigy 135 points

Part Number: TXB0104
Other Parts Discussed in Thread: AFE5818, SN74AXC4T774, TXS0104E,

1、schematic

B1~B4, OE is connected to FPGA IOs(bank2.5V); A1~A4 is connected to AFE5818.

Signal direction:

A1—>B1; SDO

B2—>A2; Tsclk=160ns

B3—>A3; SEN

B4—>A4; SDIN

AFE5818 Pin Functions:

2、wave

B2 wave	A2 wave

B3 wave	A3 wave

B4 wave	A4 wave

TXB0104RUTR_issue.docx

3、Please advise what would be the problem root cuase and how to solve this problem. Thanks.

over 5 years ago

0 Dylan Hubbard over 5 years ago

TI__Mastermind 45675 points

Hi Bill,

Thanks for the report. I noticed a common theme here: the AFE pins with internal pull-ups/pull-downs seem to be the signals having issues. And looking at the actual waveforms, I can tell which pin has a pull-down versus a pull-up. This TXB device does not like having strong pull-ups or pull-downs on the data lines, see application report below.

http://www.ti.com/lit/an/scea054a/scea054a.pdf

The best way to fix this is to use a better suited part for the job. The SN74AXC4T774 will allow you to configure the channels according to the directions you need. It's optimized to work in low voltage applications such as this one. It won't have any issues with the pull-ups/ pull-downs on the data lines.

0 faith_bill over 5 years ago in reply to Dylan Hubbard

Prodigy 135 points

Hi, Thank you for reply.

Can you provide compatible IC which has same pin definetion and footprint with TXB0104RUTR?

0 Dylan Hubbard over 5 years ago in reply to faith_bill

TI__Mastermind 45675 points

Hi Bill,

Sorry for the delay on this. Unfortunately, there isn't a pin to pin replacement part that can fix this issue. It will require a footprint change.

0 faith_bill over 5 years ago in reply to Dylan Hubbard

Prodigy 135 points

Hi,

Thank you for reply.

It will take a lot of time if change footprint（Need new PCB）, pin to pin replacement will be my first choise.

I find IC NTS0104GU12,I think them(NTS0104GU12 / TXB0104RUTR) compatible ,can you help me to check please?

0 Clemens Ladisch over 5 years ago in reply to faith_bill

Guru 316470 points

The NTS0104 is a clone of the TXS0104E. Their pinout is compatible with the TXB0104, but the electrical characteristics are quite different (the TXS/NTS use passive switches, and have internal pull-up resistors).

0 Dylan Hubbard over 5 years ago in reply to Clemens Ladisch

TI__Mastermind 45675 points

Hi Bill,

As Clemens stated, we have an identical part. I would've suggested it, but it will also have issues with pull-ups/pull-downs.

Logic

Logic forum

TXB0104: TXB0104RUTR_issue