Author Topic: The Exigo: A high performance USB charger  (Read 22466 times)

0 Members and 1 Guest are viewing this topic.

Offline brabus

  • Regular Contributor
  • *
  • Posts: 223
  • Country: it
Re: The Exigo: A high performance USB charger
« Reply #50 on: September 10, 2014, 04:16:53 pm »
Last question: do you offer any form of warranty for damages caused by your out-of-spec charger?

What's out of spec about it?

(...)

Correct if I am wrong, but I remember a 5V nominal voltage with a +/- 5% tolerance, hence 5.25V maximum, isn't it?
 

Offline NANDBlog

  • Super Contributor
  • ***
  • Posts: 4482
  • Country: nl
Re: The Exigo: A high performance USB charger
« Reply #51 on: September 10, 2014, 05:18:36 pm »
2.0 is specified 5V +/- 5%
USB 3.0 is 5V +0,25V/-0,55V (Why USB-IF, WHY??)
 

Offline Monkeh

  • Super Contributor
  • ***
  • Posts: 6023
  • Country: gb
Re: The Exigo: A high performance USB charger
« Reply #52 on: September 10, 2014, 06:00:09 pm »
Go fetch http://www.usb.org/developers/docs/usb20_docs/usb_20_081114.zip and read the VBUS ECN.

Yes, it's very recent.
 

Offline NANDBlog

  • Super Contributor
  • ***
  • Posts: 4482
  • Country: nl
Re: The Exigo: A high performance USB charger
« Reply #53 on: September 10, 2014, 06:21:56 pm »
Go fetch http://www.usb.org/developers/docs/usb20_docs/usb_20_081114.zip and read the VBUS ECN.

Yes, it's very recent.
This is interesting. Hovewer:
"OEM’s can design products that support the higher power levels of the Type-C connector and provide VBUS levels at or above 5.25V..."
So you need the type C connector for that.
 

Offline Monkeh

  • Super Contributor
  • ***
  • Posts: 6023
  • Country: gb
Re: The Exigo: A high performance USB charger
« Reply #54 on: September 10, 2014, 06:24:37 pm »
Go fetch http://www.usb.org/developers/docs/usb20_docs/usb_20_081114.zip and read the VBUS ECN.

Yes, it's very recent.
This is interesting. Hovewer:
"OEM’s can design products that support the higher power levels of the Type-C connector and provide VBUS levels at or above 5.25V..."
So you need the type C connector for that.

No, you don't, and that's not the specification, that's a reasoning. VBUS has been raised to max 5.5V, simple as.
 

Offline Monkeh

  • Super Contributor
  • ***
  • Posts: 6023
  • Country: gb
Re: The Exigo: A high performance USB charger
« Reply #55 on: September 11, 2014, 12:14:56 pm »
You mean like Samsung do with their 2A chargers? ;)

No. Samsung increase current until the voltage starts to sag below a certain level. What I suggest is that you raise the voltage above 5V so that after loss in the cable the device sees 5.0V exactly.

That's what Samsung 2A chargers do, and I have tested this. The output voltage of the charger rises with increasing current to offset the volt drop of the supplied, characterized cable.
 

Offline marcan

  • Regular Contributor
  • *
  • Posts: 80
  • If it ain't broke I'll fix it anyway.
    • My blog
Re: The Exigo: A high performance USB charger
« Reply #56 on: September 13, 2014, 02:34:52 pm »
You mean like Samsung do with their 2A chargers? ;)

No. Samsung increase current until the voltage starts to sag below a certain level. What I suggest is that you raise the voltage above 5V so that after loss in the cable the device sees 5.0V exactly.

That's what Samsung 2A chargers do, and I have tested this. The output voltage of the charger rises with increasing current to offset the volt drop of the supplied, characterized cable.

I must say this sounded way too smart for Samsung and you just made me test my 2A charger, but you're right. 5.01V at the port no load, 5.08V pulling ~1A. I'm not sure where I put the original cable right now, so I can't test it, but that sounds reasonable for a decent cable. Clever.
 

Offline grenert

  • Frequent Contributor
  • **
  • Posts: 446
 

Offline amyk

  • Super Contributor
  • ***
  • Posts: 6541
Re: The Exigo: A high performance USB charger
« Reply #58 on: September 14, 2014, 01:09:38 pm »
I must say this sounded way too smart for Samsung and you just made me test my 2A charger, but you're right. 5.01V at the port no load, 5.08V pulling ~1A. I'm not sure where I put the original cable right now, so I can't test it, but that sounds reasonable for a decent cable. Clever.
It's nothing more than a minor change to the regulation loop, even some of the cheap (but not cheapest) no-name adapters have it.
 

Offline NANDBlog

  • Super Contributor
  • ***
  • Posts: 4482
  • Country: nl
Re: The Exigo: A high performance USB charger
« Reply #59 on: September 14, 2014, 03:30:55 pm »
Ist kaputt:
https://www.kickstarter.com/projects/1386151743/exigo-usb-charger/posts
That is actually good. Looks like lesson leared.  :-+ Good luck with the redesign!
 

Offline marcan

  • Regular Contributor
  • *
  • Posts: 80
  • If it ain't broke I'll fix it anyway.
    • My blog
Re: The Exigo: A high performance USB charger
« Reply #60 on: September 14, 2014, 05:00:01 pm »
It's nothing more than a minor change to the regulation loop, even some of the cheap (but not cheapest) no-name adapters have it.
Oh, I know it's easy to implement, I'm just surprised they bothered/thought of it. I don't think any of my other adapters do it, but then again the rest are either cheapies or multiport ones (with shared regulation) where it wouldn't make sense.
 

Offline timb

  • Super Contributor
  • ***
  • Posts: 2528
  • Country: us
  • Pretentiously Posting Polysyllabic Prose
    • timb.us
Re: The Exigo: A high performance USB charger
« Reply #61 on: September 21, 2014, 10:59:17 am »
By the way, Mike was right about linear regulators being everywhere with regards to USB battery charging. LiPo charging chips come in two flavors: Linear and Switching. Go check out TI's product portfolio.

Increases voltage = increased heat = higher chance of things breaking.


Sent from my Smartphone
Any sufficiently advanced technology is indistinguishable from magic; e.g., Cheez Whiz, Hot Dogs and RF.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf