The power supply also drives a “luxury” white LED light source (LED2–LED4). Fig. 1 depicts the system block diagram of the solar window charger, whereas Fig. 4 shows the tried-and-true circuit diagram ...

This add on circuit can be attached to the solar charger to see whether the battery is charging or not. It lights a Red LED to indicate that the battery is not accepting charge. It gives a warning ...

There’s no better sign of their cost-effective ubiquity than the dollar store solar garden light: a complete unit integrating a white LED ... charge from draining back into the rest of the circuit.