Cytron Technical Forum

Hi there,

The USB port on Arduino Fio can only be used to charge battery, and not power the board.

Therefore I wonder whether I can solder a solar panel onto the Fio's charge port directly and use solar panel as a power source to charge the battery if sunlight is available?

leexin89 WROTE:The USB port on Arduino Fio can only be used to charge battery, and not power the board.

Looking at the schematic for Fio, seems like the USB port can both power up the Fio and be use to charge LiPo battery.

leexin89 WROTE:Therefore I wonder whether I can solder a solar panel onto the Fio's charge port directly and use solar panel as a power source to charge the battery if sunlight is available?

It's better to get a solar panel with regulated USB 5V output and connect it to the Fio's USB port, unless you plan to regulate (eg: buck-boost switching) the solar panel output on your own.

Hi Sich,

I beg to differ. I've tested to Fio on USB power alone and the programming/XBee won't run - unless I plug in a Li-po battery. So powering it from USB is out of the question, which comes back to my original question:

whether I can solder a solar panel onto the Fio's charge port directly and use solar panel as a power source to charge the battery if sunlight is available?

leexin89 WROTE:I beg to differ. I've tested to Fio on USB power alone and the programming/XBee won't run - unless I plug in a Li-po battery. So powering it from USB is out of the question, which comes back to my original question:

whether I can solder a solar panel onto the Fio's charge port directly and use solar panel as a power source to charge the battery if sunlight is available?

That's weird! From the schematic and the tutorial that we did for Arduino Fio, it can be powered with USB connection during program loading and during usage.

Looking at schematic of Fio, the USB power will go through battery charger become Vbatt, further go through a PTC, then the slide switch, finally to 3.3V voltage regulator and to supply the microcontroller.
Back to your question, can solar panel be used? Well, I will check the datasheet of the battery charger which is MCP73831, the maximum input voltage is 6V, so as long as you make sure the solar output does not exceed 6V, it should be working fine!