Actions
Forum Thread Details
  • State Not Answered
  • Replies 14 replies
  • Subscribers 420 subscribers
  • Views 2206 views
  • Users 0 members are here
Related

Which is better Input 5 volts to arduino..??

e14 Contributor

Guys, I intend to use arduino 24*7. I'm using it in a small industrial bot. I don't want my arduino to draw a higher current than its capability and get damaged. In my application I use 5 digital pins of my arduino as input n rest as output. To make sure OUTPUT pins does not draw more current, I've conneted it to ULN 2803 which is having further connections. I'm okay in that. I want to ask, would it be better to give the input 5 volts to the INPUT pins in my code from the "5V pin of arduino" or "from my 5 Volt regulator IC 7805". My goal is to make sure arduino works for a long period of time..!!

 

Thanks in advance.. image

Parents
  • 0

    Mr. OP,

     

       Please make clear what you are asking.   thanks.

    Pritish Shardul wrote:

     

    ... the input 5 volts to the INPUT pins in my code from the "5V pin of arduino" or "from my 5 Volt regulator IC 7805". ....

     

    Thanks in advance.. image

     

    My opinion is that it does not matter - do it either way.  But, I would like to hear from Mark Beckett on the issue.

     

    According to the data sheet for the Toshiba ULN2803A, the maximum input current draw from the 8 UNO output pins will be 8 x 0.5 mA = 4 mA at 5 Volts.  That leaves 142 mA for use on the 5? input pins.  I will guess that it should be more than adequate.

  • 0 in reply to billabott

    Thanks for your help,

     

    I was talking about giving input 5 volts to the digital pin which is assigned as input in my code.

    Not about powering Arduino through the Vin pin. I have a proximity sensor giving 12 v output. When the proxy sensor gets High, it turns on a 12v relay and thus making a contact of +5 volts to one of my digital pins (which i have set as input pin in my code) of arduino. So I was asking about this 5v supply should be external or should be from arduino 5v pin in order to ensure long term use of arduino. I hope its clear now... image 

Reply
  • 0 in reply to billabott

    Thanks for your help,

     

    I was talking about giving input 5 volts to the digital pin which is assigned as input in my code.

    Not about powering Arduino through the Vin pin. I have a proximity sensor giving 12 v output. When the proxy sensor gets High, it turns on a 12v relay and thus making a contact of +5 volts to one of my digital pins (which i have set as input pin in my code) of arduino. So I was asking about this 5v supply should be external or should be from arduino 5v pin in order to ensure long term use of arduino. I hope its clear now... image 

Children