# Travel Mobile Phone Charger Circuit

Here is an ideal mobile charger using 1.5 volt pen cells to charge mobile phone while traveling. It can replenish cell phone battery three or four times in places where AC power is not available.

## Schematic of Cell Phone Charger Circuit

travel mobile phone charger circuit schematic

Most of the Mobile phone batteries are rated at 3.6 V/500 mA. A single pen torch cell can provide 1.5 volts and 1.5 Amps current. So if four pen cells are connected serially, it will form a battery pack with 6 volt and 1.5 Amps current. When power is applied to the circuit through S1, transistor T1 conducts and Green LED lights.

When T1 conducts T2 also conducts since its base becomes negative. Charging current flows from the collector of T1. To reduce the charging voltage to 4.7 volts, Zener diode ZD is used. The output gives 20 mA current for slow charging. If more current is required for fast charging, reduce the value of R4 to 47 ohms so that 80 mA current will be available. Points A and B are used to connect the charger with the mobile phone. Use suitable pins for this and connect with correct polarity.

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##### Related Tutorials

• Gaurab

Sir,
What is the use of the capacitor connected parallel to the base of the transistor T1 ?
As we are taking in DC voltage so is it used to provide a stable voltage across base?

Thanks

• Salim

Hi sir, I did it right, but the phone start poping… It charges for milliseconds and then disconnected and then again charging for milliseconds…it keeps doing that?!

• karanam shanmukha srinivasa rao

Sir tell me how to increase the power and mAh

• suraj

Hello sir,
I m students of engineering college,I follow ur idea but I want to discover to use 9volt battery to charge mobile
And also charge this battery
It mean I want circuit diagram 3.7-5v to 9v battery charge and also discharge to left 3.7v in mobile
Pls solve my problem

• usama

Sir I made Tish circuit this give the output of4.4 V but not charge the mobile. What’s problem?

• VIVEK

SIR ,PLZ tell how to increase current without increase voltage of mobile charger.

• yamen

the output is not stable. the phone is charging and stopping many times per minute. is it ok? or i have something wrong?

• sowmya

Dear Sir,
May i know the components required for this circuit in detail.

• Tushar

Sir …the circuit gives the output of 4.95 volts but …..the required rating current fof charging a phone is atleast 350 mA …which we do not get from the above circuit …so the circuit is there not useful …it is just a voltage regulating circuit …..

• SOURABH OJHA

NICE

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