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Electronics => Electronics => Topic started by: rox2007 on January 15, 2008, 03:39:44 PM

Title: how do i supply power to my servos and atmega board using a 12v wall source
Post by: rox2007 on January 15, 2008, 03:39:44 PM
i used the voltage regulator to churn out 5v to my atmega. I wanted to test my code for my servos so i connected it to the churned out 5v and fireworks went off. i fried my atmega :(. luckily i have another one. is there a way around this or do i have to use a nimh or li battery.
thank you
Title: Re: how do i supply power to my servos and atmega board using a 12v wall source
Post by: airman00 on January 15, 2008, 04:43:49 PM
servos use between 4.8 -6 volts

either get a switching regulator for the 12V to make it into 6 volts , or just  get separate batteries
Title: Re: how do i supply power to my servos and atmega board using a 12v wall source
Post by: paulstreats on January 15, 2008, 06:46:05 PM
Did you connect the servos up right?

I regularly use servos through the regulated 5v source along with an mcu. I know youre not supposed to but i havent had any problems yet. The only thing that should be an issue is the 5v regulator, if it gets too hot it will die although they quite often just shut down until they cool off again, also an issue that ive never had with a 5v regulator - although i only ever use a 9.8v wall power sopurce or batteries.
It might be worth checking the voltage on your wall power source since mines supposed to be a straight 6v but it actually produces 9.8v. The higher your input voltage the hotter the regulator will get
Title: Re: how do i supply power to my servos and atmega board using a 12v wall source
Post by: airman00 on January 15, 2008, 07:01:26 PM
how much amps does your regulator regulate out ?

what is the part number of the regulator
Title: Re: how do i supply power to my servos and atmega board using a 12v wall source
Post by: rox2007 on January 16, 2008, 09:43:40 AM
IC REG POS 5V 1.0A 4% TOL TO-220

its the 7805.
Title: Re: how do i supply power to my servos and atmega board using a 12v wall source
Post by: airman00 on January 16, 2008, 01:07:11 PM
yea 1 amp may not be  enough for your servos( though it really should be)

did you perhaps short out the atmega???
Title: Re: how do i supply power to my servos and atmega board using a 12v wall source
Post by: rox2007 on January 16, 2008, 01:55:09 PM
i really dont know what happened, but my atmega stopped working even thought it was receiving power. i guess i'll just buy a battery pack for the servos
Title: Re: how do i supply power to my servos and atmega board using a 12v wall source
Post by: Admin on January 20, 2008, 09:07:20 PM
When you say fireworks, you mean you saw sparks?

That means you have a short somewhere in your circuit . . .
Title: Re: how do i supply power to my servos and atmega board using a 12v wall source
Post by: rox2007 on January 20, 2008, 10:56:29 PM
it was just an expression. i got 4 1.5v aa batteries for the servo