Dumb USB Charger - Just 5v DC & 200 ohm resistor on +?

USB PICs and the UBW

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danjcla
Posts: 2
Joined: Mon May 16, 2016 7:30 am

Dumb USB Charger - Just 5v DC & 200 ohm resistor on +?

Post by danjcla » Mon May 16, 2016 7:46 am

Sorry for such a basic question but I've searched for like half an hour and haven't found anything that looked 100% definitive.

I have a 12v DC power source, and then a voltage converter to 5v DC from eBay with these specs:
* Non-isolated
* Input voltage range: DC 8~23v
* Output voltage: DC 5V
* Output current: Max. 3A
* With overload/over-current protection
* With over/low voltage protection
* Stable performance.


It's charging a little basically old-school pocket organizer device called a Ben Nanonote. The Nanonote uses a Seaward Electronics SE9016 Standalone Linear Lithium Battery Charger Integrated Circuit. (their page) (datasheet). It has a USB 2.0 Mini port.

To charge do I need to do anything other than place a 200-ohm resistor between the 5v DC positive lead and the 5v positive wire of the USB cable?

Is there a way to test that the supply is charging within the USB spec (without an oscilloscope or other higher end stuff) before deployment?

Thanks for any help,
-Danny

danjcla
Posts: 2
Joined: Mon May 16, 2016 7:30 am

Re: Dumb USB Charger - Just 5v DC & 200 ohm resistor on +?

Post by danjcla » Tue May 17, 2016 5:35 am

Talking to some people elsewhere, so so far it sounds like it is safe to just try 5v on the P(ower)+ and P(ower)- lines, and then if the device doesn't charge try the 200-ohm resistor shorting the D(ata)+ and D(ata)- lines, and if that doesn't work look into the 4-resistor thing.

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