ICs like 7805, 7806, 7809, 7812, LM317, LM338, LM396, IC 723, L200 are among the popular linear regulator ICs that are very easy to configure for creating solar regulator circuits. For example, an LM317 IC can be quickly and cheaply configured to charge a 12 V batteryfrom a 24 V solar panel. But the final will be highly. It is simply because switching regulators are able to transform the excess amount of voltage or current from the solar panel into an equivalent amount. A solar battery charger using a 7805 switching regulator can be seen in the following figure: In this 7805 buck converter circuit around 80 % efficiency is achieved by the introduction of the Q1, D1 and L1. The Q1 transistor, along with the help of the blocking diode. LM317 is yet another linear regulator which can be transformed into a highly efficient solar switching regulator charger. Inexpensive adjustable. The PWM IC TL494 can be used to create a PWM switching buck converter regulator for charging batteries efficiently from solar panels. An example circuit.
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Simple solar charger circuits are small devices which allow you to charge a battery quickly and cheaply, through solar panels. A simple solar charger circuit must have 3 basic features built-in: It should be low cost. Layman friendly, and easy to build. Must be efficient enough to satisfy the fundamental battery charging needs.
You can add a diode in series with the positive wire of the solar panel. It can be a 1N5402 diode The battery can be any 3.7V 1200mAh Li-ion battery. Motor can be any 3.7V DC motor.
For example, if the open circuit voltage of your solar panel is 20V and the battery to be charged is rated at 12V, and if you connect the two directly would cause the panel voltage to drop to the battery voltage, which would make things too inefficient.
This must be precisely set such that the emitter produces not more than 1.8V with a DC input of above 3V. The DC input source is a solar panel which may be capable of producing an excess of 3V during optimal sunlight, and allow the charger to charge the battery with a maximum of 1.8V output.
In such situations the battery might need an external charging from mains using a 24V, power supply applied across the solar panel supply lines, across the cathode of D1 and ground. The current from this supply could be specified at around 20% of battery AH, and the battery may be charged until both the LEDs stop glowing.
The meter and the input diode are not included in the PCB. The second design explains a cheap yet effective, less than $1 cheap yet effective solar charger circuit, which can be built even by a layman for harnessing efficient solar battery charging.