2016-12-19 22:56 GMT+01:00 Luke Kenneth Casson Leighton lkcl@lkcl.net:
crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68
On Mon, Dec 19, 2016 at 9:45 PM, Jonathan Frederickson silverskullpsu@gmail.com wrote:
Hey, I have a few questions about the laptop housing.
- How does one connect it to power?
standard DC jack, anywhere between 7 and 19v.
I've never found a standard DC jack ;-). I presume a "dognut" type plug? If so, of what dimensions and which polarity or does it have a polarity switcher or at least a polarity safety?
I think the USB-C connector is going to be the first "standard" "universal" charging connector. Standard USB-C cable should be able to provide 60W (20V*3A) and power cables 100W (20V*5A). But not "ominous" enough yet.
Can it be powered over USB
powered no, charged, yes. current limit on the OTG port.
Well if the input minimum is 7V than neither.
But if I understood correctly the EOMA-68 card accepts power over the OTG port and passes through, any surplus, to the housing. Thus slowing down the battery drainage of the housing(laptop/tablet). And charging, although slow, when the housing is turned off. And a little faster when both, housing and card, are turned off.
Standard USB only delivers 5V*500mA= 2.5W. But various options are allowed apparently. https://en.wikipedia.org/wiki/USB#Power
or does it require a specific AC adapter?
no. min 4A is best, but if you're prepared to reprogram the STM32F072 yourself you could get away with less
4A on the output side I presume so 19v*4A=76W, So a 95W power supply with 80% efficiency (90*80%=76). Or 85W at 90%.
I have a portable solar array with a battery pack that can charge portable devices over USB, and I'm trying to work out whether or not I'll be able to power the laptop from it.
If it has 12v out that would be your best bet I guess.