PINE64
Power supply clarification - Printable Version

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+--- Thread: Power supply clarification (/showthread.php?tid=6897)



Power supply clarification - maldus - 11-28-2018

The Pinebook requires a 5V 3A power supply to charge/work.
What would happen if I used a lower power supply, like 2A or even 1A? Specifically, would it damage the device, would it charge (or discharge, if in use) the battery at a slower rate or would it do nothing at all?

I bought a USB to type H power cable to be used with a power bank (https://www.pine64.org/?product=1-meter-length-usb-to-type-h-barrel-power-cable) , and I wanted to know if said power bank needs specific requirements or I can use anything I can get my hands on.


RE: Power supply clarification - Luke - 11-28-2018

As long as the V stays at 5V you can use a lower spec PSU without worrying about damage. I suspect that 2A would still barely charge the unit when its on and it would charge it slower with the unit off.


RE: Power supply clarification - maldus - 12-10-2018

Just for the sake of paranoia, does the same apply to quick charge power supplies and 3.1 USB? I've stumbled upon this https://www.amazon.com/AUKEY-Charger-Samsung-Qualcomm-Certified/dp/B018RR30TK which promises 3A at 5V, but also 2A at 12V and so on up to 20V.
Does the Pinebook know its way around negotiating the voltage level? I'm totally oblivious to this, and I don't want to risk damaging something.


RE: Power supply clarification - Luke - 12-12-2018

I am no expert on quick chargers - I am pretty certain that they tend to not deliver the most stable current for SBCs and are therefore not recommended - but I'll point your question out to someone smarter who actually knows.


RE: Power supply clarification - meredith - 12-16-2018

Quick Charge requires negotiation over data pins, but the Type H connector has none, so it will only provide up to the USB standard maximum of 500mA until it completes negotiation for more.  You can confirm your pinebook is charging at 300-500mA in this state by checking sysfs -- it's only enough to drain the battery more slowly, not charge it.

So to use the USB-to-H wire, you actually need a "dumb" power supply like the provided wall wart that just drives 3A without caring what's on the other end.  I know some power supplies meant for SBCs like RPi are like this, but I couldn't tell you how to be sure it's a dumb supply when browsing online, except that Quick Charge or any similar standard is a red flag.


RE: Power supply clarification - maldus - 12-17-2018

Gotcha. Thanks for the clarification, much appreciated!