Can any one help me for a circuit that can take 12v 4-6A input and give an out put of 6-8v and 800mA. i am very novice to electronic. Actually i need this circuit for my camera which is using a 7.2v 800mA battery. and i want to use a 12v 4A battery to power it up. plz help me out.
Kevin Weddle
- Feb 23, 2004
- 1,620
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- Feb 23, 2004
- Messages
- 1,620
Check out the Projects section for 12V 500ma. I have given the answer to your problem. It is a simple voltage regulator that will take your input and deliver the voltage and current. This will take some design work but maybe I can steer you in the right direction. Use the TIP31A available from radioshack as the main current transistor. Use any lower current transistor as the feedback transistor. Place the feedback directly to the base of the feedback transistor. The resistor from the input to the collector of the feedback transistor will have the same value as the emitter resistor. The mid current of the feedback transistor will determine the value of the input resistor and the emitter resistor. This is all you need. You can tag on a zener if you like at the ouput. This will improve regulation.
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the marking on the battery is showing mAH, i.e. milli-ampere hour.
By dividing it with the current drawn by the unit, you can guess how much hour your unit can use (for the battery is fully charged)
So it needed not a supply to give out 800mA for your application.
Just a simple regulator circuit will do.
By dividing it with the current drawn by the unit, you can guess how much hour your unit can use (for the battery is fully charged)
So it needed not a supply to give out 800mA for your application.
Just a simple regulator circuit will do.
Ante, I recall it was not so long ago that one could not find a 9 volt regulator. We used to use these with a diode on the center pin to lift it enough to power a 9 volt circuit. Just thought I would add this advise. When tweaking on a standard value regulator for a non standard value, you can always add diodes to the ground pin to move it up or down a bit.
MP
MP
