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help me to create a simple dc circuit Answered

anyone help me to create a simple dc voltage converter circuit..?(ONLY CIRCUIT DIAGRAM)
input of circuit  :  4.8v (1.2v X 4 rechargeable cell )  or 6v (1.5v X 4 dry cell)
output of circuit  :  5v 350mA.
#.....do not use IC chip.
#.....you can select input battery(voltage) selector swich.

for my next instructable, you must help me.....


Add a 5th battery in series to what you have, then add the voltage regulator.

The image below is a very basic setup using an LM7805. Ignore the 9V show. The LM7805 will take any voltage from 7.5V up to 35V and regulate it down to 5V.

5V converter.bmp

That's limited by the thing that's taking the current. Your circuit has to supply AT LEAST 350mA. You wouldn't usually need to limit the current to a phone, the charger is built into it.

what is the voltage of C1 and C2 ?(Eg : 1.0uF 50V Electrolytic Capacitor )

Any voltage higher then the input voltage is all you need. The LM7805 can output as much a 1A so long as the voltage source offers that much or more. Batteries will allow as much current to be pulled from them ad the circuit will need. They will just heat up and explode is too much is drawn at one. But 5AA batteries can more then handle 350mA.

Check out some other related instructables if your still having trouble,


Add 1 more battery to your schematic and use an LM7805 to regulate the voltage down to 5V. Otherwise have a look at the Minty Boost and see how they use a pair of AA batteries to supply 5V over a USB connection.

can you draw the circuit diagram with 5 battery and LM7805 ?
minty boost is using ic

To answer your question, you have to specify, what you mean by 5V.
- Is it 5V +/-20% like for an analogue circuit?
- Is it 5.0V +/-5% like for a TTL/µC circuit?
- Or is it 5.00V +/-0.01% like for an ultra high precise voltage reference?
The needed circuits vary tremendously.

very simple circuit for charging a cell (nokia)
5V +/- 20% (analogue)

You have to use a chip