problems with external power supply

i cant able to run my arduino in external dc power supply.and also when i give my shield  a external power supply of 9V battery and 5V from the arduino, the battery is lasting only for 30 minutes.can i know what is happening & how can i overcome this?

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iceng2 years ago

I guess you do not understand ..... NEVER Cross connect batteries.!!!

And mark the best answer.

Wired_Mist2 years ago

I would recommend you Use a Single power source; and invest in something bigger then a 9v battery. Hook all ground together and tie the positive end on the battery to you shield's "Voltage IN" and the other end to your Arduino's "Vin" **NOT the 5V PIN!!**

If you are sold on a 9V battery keep in mind the Capacity is only in the 500-mah range (possibly 1000-mah for some lithium ion based ones) I have worked with Toy motors that consumed between 100 ma, up to almost an amp. Check the current draw if you have a multi-meter handy; If it is consuming over 250-300 ma, there's your problem.

The three classic ways to increase run time are (A) Increase Energy Storage capacity (B) Use more efficient equipment. Or (C) Limit how often the Equipment is being used.

Try some recargable AA's ! Most have a rating of 2500mah (up to 5X more then a 9V) Just wire 4 in series to get the 6V you need. You can also recharge them, a nice bonus eh?

harish.rahman.75 (author)  Wired_Mist2 years ago
thank you very cleared my doubts

Which shield ?

Which Arduino ?

What circuit ?

What are you driving with the shield ?

harish.rahman.75 (author)  steveastrouk2 years ago
i am using arduino Duemilanove w/ ATmega328 board and robo shield for L293D motor driver & i am driving just a toy motor

circuit ?

iceng2 years ago

Good wire tracing you can either break ( disconnect ) the wire or insert this regulator if you want to run it off of the 9V only.

Also if this helped a lot you can mark the best answer for me :)

iceng2 years ago

you are cross connecting your 5v to the other battery directly !

either you are not positioning jumpers correctly or do not use a proper regulator.