TXB0108: Power-on sequence requirements

Takahiro Saito

Part Number: TXB0108

Hi team,

My customer wants to power-up the device in order of VccB and VccA.
Are there any timing and voltage requirements in the power-up sequence in order not to give damage to the device?

Regards,

Saito

over 7 years ago

0 Clemens Ladisch over 7 years ago

Guru 316690 points

Section 10 of the datasheet says that "any power supply can be ramped up first."

0 Michael J Schultis over 7 years ago

TI__Mastermind 24975 points

Hello Saito-san,

Please refer to the power supply recommendations in the datasheet:

During operation, ensure that VCCA ≤ VCCB at all times. During power-up sequencing, VCCA ≥ VCCB does not damage the device, so any power supply can be ramped up first. The TXB0108 has circuitry that disables all output ports when either VCC is switched off (VCCA/B = 0 V).

Best,
Michael

0 Takahiro Saito over 7 years ago in reply to Michael J Schultis

TI__Expert 5455 points

Hi Michael , Ladisch

Thank you for your answer.

Even if VccA starts to rise in the middle of VccB powering-up,
is it no problem to the device?

Regards,

Saito

0 Michael J Schultis over 7 years ago in reply to Takahiro Saito

TI__Mastermind 24975 points

Hello Saito-san,

It may not operate properly during this state (but VCC isn't ready anyway), but it will not damage the device to do this.

Best,
Michael

0 Takahiro Saito over 7 years ago in reply to Michael J Schultis

TI__Expert 5455 points

Hi Michael,

Thank you for your quick response.
I will answer this to to my customer.

Regards,
Saito

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TXB0108: Power-on sequence requirements