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Newbie Question - Too Easy [Solved]

Posted: Sun Jul 07, 2019 2:47 pm
by RodneyChops
Hello,

Working on a gameboy zero with kite's sword lite. I have a question probably so simple for most of you, i can't seem to find it on the wiki or searching the message board.

When plugging in the sword to test it, is there a specific voltage that needs to be supplied? I have a micro usb cable, and i have many different 'power cubes' from cellphones an the like to plug it into the wall. I could also just plug it into a computer i suppose. (Not really sure what voltage any of the USB ports on the computer would supply. Incorrect voltages can damage parts?)

Many of them have different outputs, eg 5.1v 850ma. What is recommended for the kite/pi? Similarly, what sort of voltage would be proper for the battery. Looks like there are many batteries with the JST-PH2.0 connector.

https://bllutech.com/products/4aa-size- ... po-battery

This one on the store looks really convenient. It says 3.7 volts.

Thanks!
Reid from Canada

Re: Newbie Question - Too Easy

Posted: Mon Jul 08, 2019 4:28 am
by kite
My boards will work with voltages that range from 4.5-5.5v, which in within the USB spec (10% +- 5v). Any USB port that is built to spec will behave the same, so all consumer laptops/plugs/chargers all will work fine for voltage. The PCB will only pull as much current (amps) as it requires, and is recommended to use something that is 1.5A or over. If you use something that is only 500mA, charging will be fine, but run + charging will likely not work properly. Also if you didn't have a battery attached 500mA is likely not enough to power the whole thing and it will reset itself randomly (usually during boot up).

So, tldr: any USB port (approx 5v, 5.1v is fine, 5.4v is fine too!) at 1.5A or higher.

For battery, all LiPo batteries are either shown as their full capacity (4.2V) or their 'nominal' capacity (3.7v). There are 'high voltage' batteries which are 4.35V and 3.85V (respectively) which will work fine, but the charger will charge them up to 4.2V (which is fine, it's just not using the 'high voltage' support of the battery.

Hope that helps. If you're buying batteries or wiring them up yourself, CHECK THE POLARITY of the JST cable that plugs in to the board. Sometimes they are reverse (so it would plug the RED wire in to the - connector, which is WRONG). It is simple with a knife to pull out the contacts on the cable and swap them over to the right order (RED = +, BLACK = -)

Re: Newbie Question - Too Easy

Posted: Tue Jul 09, 2019 7:39 am
by RodneyChops
Very clear answer! I will be certain to check the battery polarity.

Much Appreciated!
Rodney