Go Down

Topic: POWER SUPPLY (Read 583 times) previous topic - next topic

chetan0412

Hi,

I am working on project in which i have use 7805 to supply my arduino board,

but my input supply is 12V and 10-12 amp,

does this burn my arduino?

can anyone tell me is this safe or not,

and my second question is how to convert 12v 10amp supply  to 12v 2amp supply.

mmcp42

er
you don't
the current rating is the maximum it will supply
your circuit will take what it needs
if your circuit needs 2 amps
a) is it an Arduino?!?!?
b) you need to be able to supply 2A so a 10A supply will be fine
there are only 10 types of people
them that understands binary
and them that doesn't

chetan0412

yes it is arduino.

just made one circuit to run solenoid,

but my input supply direct from battery is 12v and 10amp, thats why afraiding, does this harm to my ardino ???

i have used 7805 voltage regulator for my arduino.

Arrch


yes it is arduino.

just made one circuit to run solenoid,

but my input supply direct from battery is 12v and 10amp, thats why afraiding, dows this harm to my ardino ???

i have used 7805 voltage regulator for my arduino.


If you're trying to plug 12v into Arduino, then yes, you should be afraid.

If you've regulated the 12V down to 5V with the 7805 and are plugging the 5V into the Arduino, you are fine.

chetan0412

Hi,

Does 7805 will control 12v 10amp supply as per my arduino board requirement?

everywhere i found that, 7805 can controll 24v to 5v, but i didnt find anything about current(amp)

does 7805 will pass 10 amp to arduino?

mmcp42

the Arduino will draw whatever current it needs
stop thinking of it as a 10amp supply
think of it as a 24volt supply, with a MAXIMUM of 10 amps
there are only 10 types of people
them that understands binary
and them that doesn't

Arrch


Hi,

Does 7805 will control 12v 10amp supply as per my arduino board requirement?

everywhere i found that, 7805 can controll 24v to 5v, but i didnt find anything about current(amp)

does 7805 will pass 10 amp to arduino?


No, it will not "pass" 10 amps. If you look a the datasheet, you'll see the maximum amount of current a 7805 can supply is going to much less than 10 amps. Furthermore, I don't think you understand the concept that amps aren't "pushed", they are "pulled". In other words, your 10 amp supply isn't sending 10 amps, it's sending UP TO 10 amps. How much it actually supplies, depends on the load. If I told you I could sell you UP TO 10 chickens, that doesn't mean you have to buy all 10 of them. You can buy 2 of them if that is all you needed.

CrossRoads

The 10 amps will not be passed on. The arduino will draw the same 200mA-300mA or so that it always has (depending on your loads).
Connect the 5V/Gnd from the 7805 to 5V and Gnd on the Arduino power header.
Put a diode (1N4002 type) from 5V (cathode) to Vin (anode) so the onboard regulator is not being driven in reverse and potentially damaged.
See page 10-11
http://www.ti.com/lit/ds/symlink/lm1117-n.pdf
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

Go Up