Solar Energy Click Board™

Product Code: MIKROE-2814

How Does The Solar Energy Click Board™ Work? The Solar Energy Click Board™ is equipped with BQ25570, nano-power high-efficiency boost charger and buck converter device, designed to work with very low power energy harvesting elements. It can both provide power to the connected external load and charge the LiPo rechargeable battery using the solar panel as the photovoltaic element - employing its energy harvesting capabilities. The connected load will be powered on either from the connected LiPo battery or the supercapacitor soldered on board. When the battery voltage drops under the 2.85V, the interrupt pin (routed to the mikroBUS™ INT pin) will be driven to a LOW logic state. The integrated nano-power management unit takes care of providing the proper charging conditions for the battery. When the battery is charged up to 3.25V - due to the hysteresis set with the voltage divider resistors - the INT pin will go to a HIGH logic state, once again. Also, thanks to the nano-power management unit, the battery will not get overcharged above 4.06V.

The click board™ provides 2.6V/100mA for the connected external load on the output terminal. When the battery is not connected, the internal supercapacitor will be used as the energy storage element. This is useful for continuous powering up of very low power applications, as the supercapacitor should be able to provide power continuously since it will get recharged by the solar panel before it is drained out by the load. The internal converter will be disabled if the storage element voltage drops under the internally set under-voltage level of 1.95V, preventing the damage of completely draining out the connected storage element. In addition to the INT pin, there are two more pins of the BQ25570 routed to the mikroBUS™, used to enable the BQ25570 internal sections (EN) and to enable the power output for the connected load (OUT). Setting the EN pin to the LOW logic level will enable the BQ25570 internal sections and the power charger features, while the HIGH logic level on the OUT pin will enable the power output for the connected load. Specifications Type Battery charger, Solar Charger Applications The Solar Energy Click Board™ is an ideal solution for powering wireless sensor networks, environment monitoring devices, portable and wearable health monitoring devices and similar low power self-sustained devices On-board modules Texas Instruments BQ25570 - a nano-power high-efficiency boost charger and buck converter device Key Features Provides power to the connected external load and charge the LiPo rechargeable battery using the solar panel, provides 2.6V/100mA for the connected external load on the output terminal, the battery will not get overcharged above 4.06V Interface GPIO Compatibility mikroBUS Click board size M (42.9 x 25.4 mm) Input Voltage 3.3V Pinout diagram This table shows how the pinout of the Solar Energy Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns). Notes Pin Pin Notes External OUT enable OUT 1 AN PWM 16 NC NC 2 RST INT 15 INT Battery OK indication BQ25570 enable EN 3 CS RX 14 NC NC 4 SCK TX 13 NC NC 5 MISO SCL 12 NC NC 6 MOSI SDA 11 NC Power supply 3V3 7 3.3V 5V 10 NC Ground GND 8 GND GND 9 GND Ground Solar Energy Click Board™ Electrical specifications Description Min Typ Max Unit Energy harvesting input terminal voltage rating 0.1 5.1 V Ener