Emergency USB Charger V1.0





Introduction: Emergency USB Charger V1.0

It is a device that will charge your phone & other other devices that plugs into a USB to charge.

Make it and enjoy.

It can charge your phone up to five time in one full charged battery.

You can charge 4*3 Volt battery with your Nokia mobile charger. It will take time to charge.

Ones it is charged it is ready to charge your phone 5(approx) times. :)

Step 1: Requireed Items

You will require:

  1. LM or MC 7805 +5VDC Voltage Regulator
  2. Heat Sink(Optional)
  3. Type-A Female USB Port
  4. 100uf Electrolytic Capacitor 10-50V
  5. 0.1-0.5uf Capacitor 6-50V (any type would do)
  6. 100-160 ohm Resistor
  7. 12(4*3)V Battery(Series Connection)
  8. 2.2V 20mA LED color of your choice
  9. Bread board
  10. Pref Board
  11. 3 Pin Switch...etc which are present in picture

Step 2: The Circuit Diagram (Simple)

The following picture shows the sketch diagram of Circuit which we want to make.

Step 3: Attaching the Components

First attach all the components on Bread Board and check the output(O/p) is 5V by Multi-Meter or we have 5V O/p Checker. Then Place it on PVC Board and solder it with the help of soldering components Like the picture.

Step 4: Adjustment

Do some holes in the box for switch, Charging Point and USB Hub. Do some adjustment in your box and make it fixed with the help of Hot Glue Gun.

Step 5: Done! ;)

Now that you've finished building your own USB charger, all you have left to do is to put batteries in box and use it.

Remember when you add batteries in series then it will give you sum all voltage and if you connect all batteries in parallel then it will give you sum of all Amp. .

Ones it is charged it is ready to charge your phone.... ;)

Step 6: Demo!

Check It out...... It's Working Properly....

Step 7: Ugrade

In this step you will see a how to upgrade you USB Charger..

Since when you insert your charger and switch is not on then charger LED and capacitors are taking voltage from your battery.

So we put a Zener Diode or an Ideal Diode to save your battery. Here I used Zener Diode of 12 V.

Now question Comes What is an Ideal Diode and Zener Diode??

An Ideal Diode is a diode which allows current to flow in the forward direction but not permits it to flow in the reverse direction.

A Zener diode is a diode which allows current to flow in the forward direction in the same manner as an ideal diode, but also permits it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage", "Zener voltage", "avalanche point", or "peak inverse voltage".

Do connection as like in picture first........



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    Great idea! Thank you for creating and sharing this instructable.

    there were lot of project like this i just made a change little bit. hope you like it. :)

    Wow I love the idea of this, it's so useful in the modern day and age. Seems like my devices are always dying... Awesome job showing each step!

    I'm glad you liked my work and I appreciate your confidence in me.

    The 90% value is = 0.9
    The 80% value is = 0.8
    This value were derive from "how the battery generates its preserve power.The formula can be found on
    Yoobao FAQ site
    (powerbank manufacturer in China).Hope that clarifies your querries.

    15, 8:14 AM.jpg

    Thanks a lot man i will remember the calculation...

    What do you think if i add 3 more batteries of series connection in parallel to other three then the O/p comes 12V and 7000mAp. can we do this to charge any phone more times.