Pages: [1]   Go Down
Author Topic: Arduino Uno Standalone Power  (Read 1567 times)
0 Members and 1 Guest are viewing this topic.
Durham UK
Offline Offline
Full Member
***
Karma: 1
Posts: 169
aka Craig Turner
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

Hi,

I'm new to Arduino. Had an Arduino Uno (with Atmel ATMEGA328P-PU) about a week now. Does anyone know how much power the Uno uses on it's own with no project attached to it?
Does it depend on the power supply  - I want to use a good quality 9v battery I wonder how long it will power the standalone board for even before I add stuff?

Cheers
Logged

Craig Turner, blog: http://gampageek.blogspot.co.uk/ It helps with my learning if I write things down, esp. for others to follow (constructive comments welcomed to improve)

Manchester (England England)
Offline Offline
Brattain Member
*****
Karma: 639
Posts: 34726
Solder is electric glue
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

It takes about 30mA at 5V so the power is 0.15W. But do you mean power because you also have to calculate what the regulator takes.

Quote
I want to use a good quality 9v battery
Bit of an oxymoron, I don't think they exist.
Logged

Durham UK
Offline Offline
Full Member
***
Karma: 1
Posts: 169
aka Craig Turner
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

Thanks for the tip.

Would it be better to use 2x 3.7v mobile phone batteries I have (1400 mAh each) to give 7.4v?

I think I should mean current as opposed to power so I can do: mAh / Uno_board_ current_consumption (including regulator)

Would the regulator use a lot at 7.4v?

Logged

Craig Turner, blog: http://gampageek.blogspot.co.uk/ It helps with my learning if I write things down, esp. for others to follow (constructive comments welcomed to improve)

Manchester (England England)
Offline Offline
Brattain Member
*****
Karma: 639
Posts: 34726
Solder is electric glue
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

Quote
Would it be better to use 2x 3.7v mobile phone batteries
Yes defiantly.

Quote
Would the regulator use a lot at 7.4v?
Not sure what you mean. A regulator drops the voltage from the input down to (in this case) 5V. It needs a few volts at the input over the final regulated voltage to work. So changing that input voltage from 9V to 7.4V will make the system more efficient as the regulator has less power to burn off in the form of heat.
Take a look at this:-
http://www.thebox.myzen.co.uk/Tutorial/Power.html
Logged

Central MN, USA
Offline Offline
Tesla Member
***
Karma: 76
Posts: 7305
Phi_prompt, phi_interfaces, phi-2 shields, phi-panels
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

There are switching voltage regulators that waste less power when converting from a higher voltage to 5V. I'm not sure what part number. I'm saying this just to ring a bell to those that do know a part number or two. There could be a part that has the same size as the UNO's regulator and you can replace it with the switching supply for your project to last longer.
Logged


Pages: [1]   Go Up
Jump to: