Type C cables & powerbank

[bluesofa]

My wife decided to replace her mobile phone. She now has a Samsung A71 with a 'fast' charger - USB type C > type C lead.

We also have a powerbank that's been working fine for months.

I can't get the A71 phone to charge from the powerbank if using a type C > type C lead. It's fine if using a USB A > type C lead.

 

I can charge the powerbank using the powerbank type C port, to her A71 charger (and  it's obviously faster).

The powerbank ports are USB A (x2), micro-USB (marked "IN"), type C USB (marked "smart")

I did a search and a Nexus user seemed to be having exactly the same issue as me. Is there some reason for this with powerbank type C ports?

[JayClay]

Is the type C supposed to provide power to devices? Or is it intended only as an input for charging the power bank?

 

(edit)

I just saw that the C port is labeled as "smart" so I guess it is indeed supposed to be bi-directional...

Edited January 29, 2021 by JayClay

[jackdd]

No idea why it's not working, but there is also not much you could do about it, besides of buying a different powerbank.

But I don't see how this matters much anyway, just use a type A -> type C cable and you are good.

Edited January 29, 2021 by jackdd

[bluesofa]

3 minutes ago, jackdd said:

No idea why it's not working, but there is also not much you could do about it, besides of buying a different powerbank.

But I don't see how this matters much anyway, just use a type A -> type C cable and you are good.

Yeah, I realise that.

I'm interested in discovering whether there's a compatibility issue with powerbanks when using type C> type C.

Plus my wife, now she's realised how much faster it is to charge using the 'fast' charger, is frustrated the powerbank is slower than the new mains charger.

The previous Samsung phone and charger (USB A>micro USB) was 1.55A, the new one is 3.0A, hence the type C USB lead designed to carry a higher current.

[jackdd]

Most powerbanks (at least the better ones) provide 2.4A on the Type-A ports (5*2.4=12W). If your powerbank provides 3A (5*3=15W) on the Type-C port this would only be a bit faster.

According to Google the Samsung A71 supports "5V/3A, 9V/2.77A, and 11V/2.25A", assuming this is what the stock charger outputs, it means the phone is getting charged with 25W. That's 60% faster than the best case scenario with your powerbank, it would always feel slow. I think powerbanks able to provide 25W are rare though.

[bluesofa]

12 hours ago, jackdd said:

Most powerbanks (at least the better ones) provide 2.4A on the Type-A ports (5*2.4=12W). If your powerbank provides 3A (5*3=15W) on the Type-C port this would only be a bit faster.

According to Google the Samsung A71 supports "5V/3A, 9V/2.77A, and 11V/2.25A", assuming this is what the stock charger outputs, it means the phone is getting charged with 25W. That's 60% faster than the best case scenario with your powerbank, it would always feel slow. I think powerbanks able to provide 25W are rare though.

Yes, that's exactly what it says on the A71charger itself: Model EP-TA800 Output [email protected].

 

Elsewhere it was suggested to try pressing 'on' the power button of the powerbank, immediately before plugging it into the phone. I did try that, but it had no effect. It's a pity the type C port isn't as 'smart' as the label says it is!

Looks like it's down to using the type A>type C lead.

Thanks.

[bluesofa]

I've come across some info regarding 'shortcomings' of USB type C connectors. It appears they are not all the same:

https://www.howtogeek.com/353410/3-problems-with-usb-c-you-need-to-know/

and

https://usbccompliant.com/