Is there any delay requirement for power supply sequencing for c5535 new usb power steps?

j-breeze

Hi Champs,

A new steps was added to power supply sequencing for USB_VBUS, USB_V DDA3P3, USB_V DDA1P3, and USB_V DD1P3 in the latest c5535 datasheet SPRS737C.

So, is there any delay requirement b/w the power supply ramp steps?

Thanks in advance for your cooperation.

Regards,
j-breeze

over 9 years ago

0 Sivaraj Kuppuraj over 9 years ago

TI__Mastermind 35645 points

Hi,

Your request would be addressed shortly by experts across the team.

Thanks & regards,

Sivaraj K

0 Steve Tsang over 9 years ago in reply to Sivaraj Kuppuraj

TI__Mastermind 23785 points

Basic recommendation is for these voltages to reach their minimum recommended operating conditions in that order. As such, scope these signals for their rise time, for eg. if their rise time angle are pretty much the same, then they can be pretty much one after the other. Otherwise, adjust per your system enviroment.

Hope this help.

0 Vasantha K over 9 years ago in reply to Sivaraj Kuppuraj

TI__Genius 12575 points

Hi,

If the USB is used, the subsystem must be powered up in the following sequence:

1. USB_VDDA1P3 and USB_VDD1P3

2. USB_VDDA3P3

3. USB_VBUS

There is no delay requirement as such, as long as the supply bus is powered up to the recommended operating voltage range.

Also refer to the wiki page on USB hardware design guide.

http://processors.wiki.ti.com/index.php/OMAPL1xx,_AM1xx,_C674x,_DA8xx_USB_Hardware_Design_Guide

Hope the above helps.

Regards

Vasanth

0 j-breeze over 9 years ago in reply to Vasantha K

Mastermind 7560 points

Hi Steve, Hi Vasanth,

Thank you for your support.

I understand there is no delay requirement.
So, I'd like to get any power supply reference designs for the latest c5535 datasheet.
Can I have any information or docs about the reference designs?

Regards,
j-breeze

0 Steve Tsang over 9 years ago in reply to j-breeze

TI__Mastermind 23785 points

The closest I can think of is the C5517 EVM. Please note that this is NOT a reference design but just an evaluation module:

http://www.ti.com/tool/tmdsevm5517

Regards.

0 j-breeze over 9 years ago in reply to Steve Tsang

Mastermind 7560 points

Hi Steve,

The schematics that you told me are very useful information.
Thank you for your support.

Regards,
j-breeze

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Is there any delay requirement for power supply sequencing for c5535 new usb power steps?