DAC5687 Power Up Sequence

Brian Berner

Other Parts Discussed in Thread: DAC5687

In looking at the datasheet for the DAC5687, it says in the "Absolut Maximum Ratings" section that AVDD (3.3V) should never be more that 2.6V above DVDD (1.8V) or 0.5V less than.

But in the "Power-Up Sequence", it states that DVDD should be powered up first. If this occures, then AVDD will be 1.8V less than DVDD, which seems like it breaks the Absolute Maximum Rating rule.

Am I reading this correctly? And if so, should the Power-Up Sequence be followed or is this potentially harmful?

Thanks!

-Brian

over 13 years ago

0 Matt Guibord over 13 years ago

TI__Genius 17340 points

Brian,

Follow the power-up sequence listed in the power-up sequence section. The absolute max table is listed incorrectly.

Regards,
Matt Guibord

0 Guido van Veldhuizen over 13 years ago in reply to Matt Guibord

Intellectual 340 points

Thank you Matt,

Would you be able to answer the second half of the question as well?

Also, since my IOVDD is 1.8V, can I bring DVDD and IOVDD up at the same time (i.e. the same 1.8V power supply powers DVDD and IOVDD)? I would then plan to bring up the 3.3V supplies after that.

Thanks..

0 Kang Hsia over 13 years ago in reply to Guido van Veldhuizen

TI__Guru* 78614 points

Hello Guido,

The DVDD will need to brought up first before IOVDD. After DVDD is brought up, you can bring up IOVDD and AVDD in any order. Please see the power up sequence section for detail.

-KH

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DAC5687 Power Up Sequence