TXU0304-Q1: Check with spec (replace SN74LVC2T45-Q1)

Roy Chou1

Part Number: TXU0304-Q1
Other Parts Discussed in Thread: SN74LVC2T45-Q1, , TXU0104

Hi Team,

We found our latest device which is called TXU0304-Q1. It's good to our our application. We used SN74LVC2T45-Q1*2 as buffer in our past application. We would like to change to use this device.

Our protocol is similar to SPI and the data rate is 50Mbps. I think TXU0304-Q1 could handle it, but I'm not sure whether there is any other spec that we need to check. May you give me some comments?

Regards,

Roy

over 2 years ago

0 Roy Chou1 over 2 years ago

TI__Genius 12635 points

Team,

For direction requirements. we select TXU0104.

0 Roy Chou1 over 2 years ago in reply to Roy Chou1

TI__Genius 12635 points

Hi team,

I have another question need your comment. We used buffer because our application has long bus cable. So do you think that we place the buffer nearest our connector or cable -> connector -> trace ->buffer?

Roy

0 Clemens Ladisch over 2 years ago in reply to Roy Chou1

Guru 244020 points

The only relevant difference is that LVC/LXC devices have a higher drive strength than TXU/AVC/AXC devices. For long cables, this might be important, but it is hard to predict; you probably have to make measurements yourself.

If you need to keep noise from the cable out of your board, minimize the distance between the connector and the buffer.

0 Roy Chou1 over 2 years ago in reply to Clemens Ladisch

TI__Genius 12635 points

Hi Ladisch,

May we let me know if there is any drive strength spec could be reference?

Roy

0 Clemens Ladisch over 2 years ago in reply to Roy Chou1

Guru 244020 points

The drive strength can be seen in the test conditions for V_OL/V_OH.

0 Roy Chou1 over 2 years ago in reply to Clemens Ladisch

TI__Genius 12635 points

Hi Ladisch,

Thanks for information. Our signal frequency is around 25MHz and the signal trace length from from buffer output on PCB is around 20inch. Do we have any simulation tool to check if the 12mA drive strength is enough or not?

Roy

0 Clemens Ladisch over 2 years ago in reply to Roy Chou1

Guru 244020 points

Sorry, I guess any drive strength is OK. You are probably doing impedance matching for the long cable. This means that you are increasing the buffer's output impedance anyway, so using a buffer with lower output impedance would just result in a higher series resistor.

0 Roy Chou1 over 2 years ago in reply to Clemens Ladisch

TI__Genius 12635 points

Hi Ladisch,

Thanks for information. We will put the termination resistor to achieve impedance matching.

Roy

0 Dylan Hubbard over 2 years ago in reply to Roy Chou1

TI__Mastermind 42670 points

Hey Roy,

I recommend using the IBIS model that can be found in the product folder. This will help simulate signal integrity for your intended load.

Logic

Logic forum

TXU0304-Q1: Check with spec (replace SN74LVC2T45-Q1)