TPS65131: USB-C VBUS protection

Benjamin

Part Number: TPS65131
Other Parts Discussed in Thread: TPS7A39, TPS25810

Hello,

I have device which is powered by 5V from the VBUS line of a standard USB-C charger. It works well, but I’m not 100% familiar with USB power standards, or what possible failures could occur in the real world.
I want customers to be able to power it from any compatible USB-C port.

Relays current draw: 120mA
TPS65131 current draw: 660mA
Total current draw: 780mA

My questions are:

1. What (if any) protection do I need on the in coming VBUS line? I have installed a PTC and TVS Diode, but I'm not sure how helpful that is in this situation.

2. Is the flyback diode across the Relay coils enough protection for the power host?

Thanks a lot!
- Ben

10 months ago

0 Patrick Yao 10 months ago

TI__Mastermind 28470 points

Hi Ben,

I am not so familiar with USB-C too, but from the TPS65131 side, it needs the input voltage to be stable during load transient. So I think you'd better to provide enough USB-C current capability.

Patrick

0 Benjamin 10 months ago in reply to Patrick Yao

Prodigy 250 points

Hi Patrick,

Thanks for your answer. Since you have stated that you are not familiar with the topic, and haven't answered my questions, would you suggest I ask this question in another e2e forum, or is there someone else who might be able to answer my questions?

Thanks
- Ben

0 Zhiqian Wu 10 months ago in reply to Benjamin

TI__Mastermind 22575 points

Hi, Ben

Our expert is OoO, and will reply you tomorrow.

0 Benjamin 10 months ago in reply to Zhiqian Wu

Prodigy 250 points

Hi Zhiqian, I just wanted to check if there was any update from your expert(s)?

0 Patrick Yao 10 months ago in reply to Benjamin

TI__Mastermind 28470 points

Hi Ben,

Do you have the spec of this USB-C charger? Is there any TI IC related?

Patrick

0 Benjamin 10 months ago in reply to Patrick Yao

Prodigy 250 points

Hi Patrick,

Patrick Yao said:
Do you have the spec of this USB-C charger?

I want it to work with all USB-C chargers, that's why I wanted to ask someone with an understanding of USB-C Standards.

Patrick Yao said:
Is there any TI IC related?

Yes! Currently TPS65131, but I'm also asking for product recommendations (if needed) that would protect the charger and/or my device.

0 Patrick Yao 10 months ago in reply to Benjamin

TI__Mastermind 28470 points

Hi Ben,

I mean the TI device that used in the USB-C charger, if you know any TI devices related, you could post a thread for our related product line to support you.

Patrick

0 Benjamin 10 months ago in reply to Patrick Yao

Prodigy 250 points

I guess I am not going to get a helpful answer, but I must say this is really disappointing. I switched to using almost only TI ICs in my designs, mostly because this forum has been really helpful for designing and getting product recommendations from experts when necessary. I find it hard to believe that TI can't find someone who understands the standards of USB-C, to help me as I upgrade my design to use even more TI chips. (My old design didn't use TPS65131 and TPS7A39 for example)

There are so many products like TPS25810 that might be suitable for me (I don't know). But I guess I won't find out from TI.

0 Patrick Yao 10 months ago in reply to Benjamin

TI__Mastermind 28470 points

Hi Ben,

What I mean is you could post a new E2E thread based on any USB-C device from TI, then the thread will be automatically forwarded to related experts and you will get their support on USB-C charger. Please understand that you post this thread with TPS65131, so it was forwarded to me, but the USB-C is from the different product line in TI.

So I suggest you post a new thread, and you can also paste the new thread link in this thread so I can know who are supporting USB-C devices and I can contact them internally to further accelerate this process.

Patrick