The board is based on a charger for Li-ion batteries and a DC-DC converter to supply the 5V. the SquidBee mote needs, and includes three different inputs: a couple of pin connectors (VCC and GND) for more than 6V cells, another couple of pin connectors for up to 6V cells and a mini USB connector. The two last connections go directly to the battery charger, but the first one goes through a voltage regulator whose output is limited to prevent the charger from any damage caused by a too high voltage. The mini USB connector has been added in order to allow the battery to be charged when it is not possible neither to attach a solar cell or to connect it to the main power.
We have selected a MAX1555 charger from Maxim to energize the battery. This module can handle two different inputs, one that bares voltages from 3.7V. to 7.0V. that will be used to charge the battery from a DC source and another one that bares voltages from 3.7V. to 6.0V., used to carry out the charge from the USB. The MAX1555 output to the battery provides a typical charging current of 280mA and a voltage of about 4.2V, though it may change depending on the battery and its state.
A MAX1674 converts the 3.7V. that we approximately have in the output of the battery into the 5V. the SquidBee mote needs to work. This device bares an output current up to 300mA, which should be more than enough to supply the mote whatever the sensors you have added.
We have also placed some capacitors of 100nF and 47uF in the inputs and in the output to the SquidBee in order to prevent noise from entering the circuit through the supply source.
For connecting the Solar module to Arduino, we'll use two wires, one of them for 5V and the other for ground (GND). In the Solar module for Arduino we'll connect these cables to Output connector, in Arduino we'll use 5V and GND pins.
Here's an explanatory video, which shows the whole process developed in this tutorial:
Solar Module for Arduino is a small board that can power your Arduino board, to get a totally autonomous outdoor board. It includes a 3W solar panel that provides 5V to your Arduino board, and a 1100 mAh Li-Ion battery.
5V Regulator Module for Arduino provides 5V to your Arduino board with a 1100 mAh Li-Ion battery.
You can download our Fritzing libraries from this area.