TXB0102: Design Query

Abhishek Manoj

Part Number: TXB0102
Other Parts Discussed in Thread: TXS0102

Hi Team,

I was planning to use the TXB0 series level translator in the design.

The TXB0102 is an auto-direction level translator intended for push-pull buses. However, it is generally not recommended for control signals that include:
• Pull-up or pull-down resistors
• Long trace routing
• Slow signal edges

Since the current design includes pull resistors and isolators in the signal path, a TXS0102 or a simple buffer is typically preferred in such cases.

Could you please confirm whether I can proceed with the TXB series level translator, or if it would be better to select the TXS series for this requirement

Regards,
Abhishek

3 months ago

0 Abhishek Manoj 3 months ago

Intellectual 835 points

Hi Team,

I want to use the TXS part level translators also for JTAG and UART interface. Please whether this level translator is ideal for those interfaces.

Regards,

Abhishek

0 Jack Guan 3 months ago

TI__Guru 56651 points

Hi Abhishek,

I would recommend using the TXU0x02 for the applications described. The TXS0102 is also an autobidirectional translator that isn't going to provide the buffering capability that you are looking for.

Regards,

Jack

0 Abhishek Manoj 3 months ago in reply to Jack Guan

Intellectual 835 points

Hi Jack,

The part TXU0x02 is unidirectional as i can't use for my directional application.

Regards,

Abhishek

0 Abhishek Manoj 3 months ago in reply to Abhishek Manoj

Intellectual 835 points

Hi Jack,

Please ignore the previous reply.

For bidirectional applications, whether TXB or TXS is preferred.

Regards,

Abhishek

0 Jack Guan 3 months ago in reply to Abhishek Manoj

TI__Guru 56651 points

Hello,

Generally speaking, UART/ JTAG signals are fixed direction per channel, in which the TXU0x02 can be used:

However, if different from your case, and a simple buffer is not hard requirement, the TXB0102 can be suggested here thanks.

Regards,

Jack

0 Abhishek Manoj 3 months ago in reply to Jack Guan

Intellectual 835 points

Hi Jack,

Thanks for the confirmation.

For my JTAG and UART signal, i will use TXU0 series level translators.

For my Digital IO signals which may may pull up in between. For these whether TXS or TXB is preferred.

Below mentioned is my query.

"TXB0102 is an auto-direction translator intended for push-pull buses.

It is not recommended for control signals with:

• pull resistors

• long traces

• slow edges

Given the design includes pull resistors and isolators, a TXS0102 or simple buffer would normally be used instead.?"

Please suggest the level translators and also mention why is better in my case, so that i can justify the query.

Regards,

Abhishek

0 Abhishek Manoj 3 months ago in reply to Abhishek Manoj

Intellectual 835 points

Hi Jack,

One more query regarding TXU0x.

For the TXS series, the datasheet specifies that VCCA must be less than or equal to VCCB. For the TXU0x series, is there a similar requirement, as it is not explicitly mentioned in the datasheet?

Regards,

Abhishek

0 Jack Guan 3 months ago in reply to Abhishek Manoj

TI__Guru 56651 points

Hi Abhishek,

For auto bidirectional signals that use push-pull drivers, TXB can be used, however if the drivers are open-drain based, then the TXS is suggested instead. Please refer to each device datasheet for switching ch./ operating voltage to ensure compatibility with your application.

www.ti.com/.../6055993170001

The TXU0x0x does not have the VCCA> VCCB restriction so it is acceptable for the VCCA voltage to be greater than VCCB.

Regards,

Jack

0 Abhishek Manoj 2 months ago in reply to Jack Guan

Intellectual 835 points

Hi Jack Guan

As you have suggested TXU for the JTAG signals. As TXU has internal pull resistors, does it affect the JTAG signals. Or should i proceed with TXS part.

Regards,

Abhishek

0 Jack Guan 2 months ago in reply to Abhishek Manoj

TI__Guru 56651 points

Abhishek,

The pulldowns on the TXU are very weak (>1Mohms). I do not see any concerns with it affecting JTAG signals.

Regards,

Jack

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TXB0102: Design Query