With the ultra low power capabilities of the trigBoard, it only makes sense to match it up with solar power! The trigSolar board was specifically designed with trigBoard in mind for both outdoor and indoor solar applications.

• Based on the Texas Instruments BQ25570RGRR Energy Harvesting IC with MPPT (Maximum Power Point Tracking) and <1uA Quiescent Current Draw. Configured for 80% MPPT by default (most common for solar panels)
• Built-in 2.5F High Quality Super Capacitor - allowing for continuous charge/discharge cycles with minimal degradation across a wide operating temperature range. Can be operated with only a super capacitor making for a battery free IoT system!
• Charge voltage set to 5V, but can be customized with simple component changes
• Automatic Switchover circuit to battery backup for mission-critical applications, in situations where the super capacitor may fully deplete. A “DETECT” output signal can be wired to trigBoard (or other host processor) to indicate if on battery backup or solar power NOTE: Battery backup is purely optional and the board does not charge this battery, which is why it can be any battery within 2-5V. Could be 4.2V lithium cell or a set of AAA batteries. The board simply gives a smooth uninterrupted switchover to the battery to ensure the notifications continue being sent. This is a clever circuit because it’s not just a “highest voltage wins” kind of circuit like OR’ing diodes, but rather a priority circuit so that it will always use solar power if it’s able to, even if the solar power voltage is less than the backup battery voltage.
• Pre-Charge Button to allow users to charge the super capacitor directly from the battery to set an initial condition for the system - also note that the trigSolar board operation requires >1V of charge on the super capacitor at all times. This would naturally occur under normal solar charging, but to “kickstart” the board, can simply just hold the precharge button for a few seconds or until the output is enabled.
• Board designed with modifications in mind - JST PH2.0mm connectors for all connections into the board as well as through hole test points, making it easy to wire into custom applications. Also, components spread out in 0805 packages, so can be replaced “easily” to set the board’s various parameters and thresholds for some custom system. Note that it works great out of the box with trigBoard!
• Super Capacitor can be expanded with simple “reserve’ circuit, so the high quality 2.5F capacitor handles the high current loads during wakes, but a much larger and lower quality capacitor can be used as reserve storage to slowly replenish the system’s charge.
• Indoor PowerFilm Solar Panel LL200-2.4-75 with pre-soldered JST Cable available as option (thoroughly tested here with indoor lighting)
• Lower cost Outdoor panel option (30mm x 38mm) - smaller and cheaper is all that’s needed with outdoors - the trigSolar board is incredibly efficient.
• Fusion360 Design here https://a360.co/3ftcq1X pw is trigsolar and you can also download the step file there as well