Hello friends I made a very simple but very useful
system for smartphone. This is a simple Emergency power-bank com portable speaker cum Torch in one box.
You can also charge your smart phone in same time of use other. You can seen my making Video on YouTube
Step 1: Parts Needed
2 -4 ohms speakers
3 -Li-Po battery 5000mAh
3 -On/Off Switches
5 -White LED,s for Torch
1 -USB female pin
1 -DC Jack Female male
This block diagram complete with switches . I am connect the DC Jack with battery pack for charging . Similarly connect all circuit line by line with switches. 3 Switches use for 3 modes of the system control by your uses. The amplifier is very low cost with simple Technic and very low cost because they used TDA2822 who control 4 ohms speakers using 470uf 25v capacitor. Second side the simple powerbank is using LM7805 the common 5v regulator for charger connect with USB female pin and switch and the simple white LED,s Circuit for torch using 56ohms resistance for more brightness .
Step 3: Make a Box Connect All on It
You can print with 3D Printer. Make a cardboard box and connect all electronic with superglue.
I made a perfect square box and connect amplifier with speakers ,Charger circuit and Torch circuit in Left Side.
Step 4: Complete+Enjoy
Now enjoy speakers in party ,celebration ,picnic and more and use power-bank and Torch to good. I made totally low cost system for smartphone. The total cost of this system 8$-10$. If you have any problem so comment on My YouTube Video and Instructable. There is my full making tutorial Link1 - Power bank