3 Smartphone Solar Charger




About: I am Science Lover . I am technology Lover.

Hello Friends toad I made a some spacial for free energy lover. All you-tubers make free energy smartphone charger with DC Motor but this project not work well.

Solar is a very highest part of renewable energy. My Solar Charger Work with 3 voltage regulator LM7805 and I use 10.72 volts solar panel.

My Solar charger can charge up-to 3 smartphone in happy sunny weather. This is simple way to save electricity. I am fixed my solar panel in my roof and at morning 8'O clock start my solar panel automatically and evening 4'O clock solar automatically switched off.

You can also use 12 volts and 15 volts solar panel for more speed.

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Step 1: Parts Needed

1 X 10.72 Volts Solar Panel Amazon

12 Volts Solar Panel Amazon

15 Volts Solar Panel // you choose any one

2 X 4700uf 25v

3 X LM7805 Voltage regulator

3 X USB Connector

3 X 4148 Zener Diode

1 X Heatshink

Step 2: Circuit Diagram

The circuit is very simple to make you can use PCB for this project.

Follow the circuit diagram step and build the circuit. This is very simple voltage regulator LM7805 .

First make circuit than fix the heatshink. If your Solar Panel makes Ac voltage so connect 1N4007 Diode in starting of connection.

Step 3: Know More Voltage Regulator

Linear Regulators. One of the most basic ways to regulate voltage and provide a stable voltage for electronics is to use a standard 3-pin linear voltage regulator such as the LM7805, which provides a 5 volt 1 amp output with an input voltage at up to 36 volts (depending on the model).

Step 4: Join Us.

So Friends if yore solar smartphone charger work well, than comment and any problem also comment me.

Go to my new website for more best projects Truescience22 and know more about interesting technology to go my new facebook page Facebook .



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    6 Discussions


    1 year ago

    Have you considered using switching mode regulator instead of linear regulator? With linear regulating you are wasting over half of the energy you collect from the solar panels. And if you really want to get the maximum performance out of your panels, you should look into regulators with maximum powerpoint tracking capabilities.


    1 year ago

    which regulator to use to get 2.5 amps output for each device?

    2 replies

    Reply 1 year ago

    Hi. You can use a LM123A or LM323A. Both are 5V 3Amp linear regulators in the TO220 package (Same as the LM705)


    1 year ago

    That's a neat charger, I like the idea of running them off a solar panel. :) How long would it take to charge?

    1 reply

    Reply 1 year ago

    The lm7805 can supply 1 Amp (1000mA) maximum (preferably with a heatsink). A 20 Watt solar panel rated at 18V open voltage output can typically supply around 1100mAh. It would therefore charge a typical mobile phone battery of 2000mAh in around two hours provided the solar panel has sufficient sun and there is no other significant loses. I would rather expect around 2.5 ~ 3 Hours in practice.