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1. 

   edpell
   Member

   Hi, can you explain the four power jumpers or point me to the documentation? Thanks. What I would like to do is solar power (through external) and battery charge during sunny times and battery power otherwise. I would like to do this without changing the jumpers.

   Posted 5 years ago #
2. 

   okie
   Administrator

   Here's a diagram of the power jumper:
   o o CHRG
   o o BAT
   o o USB
   o o EXT

   Placing a jumper to connect the two pins in the CHRG row connects the battery charger to VIN. VIN is the first column of pins. A jumper is placed to connect either BAT, USB, or EXT (the barrel jack) to connect one of those to VIN. VIN goes to the voltage regulator that outputs 3.3V, which is called VCC.

   If you want to have the battery charger connected, then you need a jumper on the CHRG row. If your solar power offers more than the battery voltage when it's on, then this circuit might work for you:

   http://static.leaflabs.com/okie/maplewithswitchingdiodes.jpg

   Here's a diagram of the circuit in the picture:

   o-o CHRG
   o-|<-o BAT
   o o USB
   o-|<-o EXT

   "-|<-" is a diode and "-" is a jumper.
   This configuration should connect the higher voltage of BAT and EXT to VIN. You then connect EXT to your solar panel. I tested it with a 9V power supply and 5V from USB, and it worked. Something like this may become part of the Maple schematic to possibly eliminate the jumper in the next revision.

   Posted 5 years ago #
3. 

   okie
   Administrator

   I used 1N4148 switching diodes.

   Posted 5 years ago #
4. 

   okie
   Administrator

   BTW, the board printed on the paper in the photo is a sneak preview of the Maple Mini prototype.

   Posted 5 years ago #
5. 

   edpell
   Member

   Thanks.

   Posted 5 years ago #
6. 

   rednaxela
   Member

   I'm interested in using diodes in this setup, but isn't the voltage drop from those too high for the lipo battery? What about Schottky diodes?

   Posted 4 years ago #
7. 

   soundcyst
   Member

   Something like this may become part of the Maple schematic to possibly eliminate the jumper in the next revision.

   +1 for this feature request.

   Posted 4 years ago #
8. 

   poslathian
   LeafLabs

   shotkeys are the way to go, and currently folded into maple mini and maple native. This will be on the next batch of Maples too.

   Posted 4 years ago #

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