Hello i have a Question is there a way to say if i have a power adapter on my uno fails is there a way to have a battery backup take over when my main power is dead? also if there is a way to charge that battery from the main power adapter ? some kind of switching power and charging of some kind.
Joseph
You could make a sort of UPS that feeds the Arduino.
This has been done before - http://forum.arduino.cc/index.php/topic,7487.0.html -
please note the warnings in that thread - DO NOT DUAL POWER!
robtillaart:
Please note the warnings in that thread - DO NOT DUAL POWER!
Ummm - why not? What will happen?
Paul__B:
robtillaart:
Please note the warnings in that thread - DO NOT DUAL POWER!Ummm - why not? What will happen?
What I think is meant in the article is that you should not put the LIPO and the wall wart in parallel to power the Arduino.
I've never tried it and I am no EE but I assume things might get a bit warmer than intended.
robtillaart:
What I think is meant in the article is that you should not put the LIPO and the wall wart in parallel to power the Arduino.
That would be bad, no doubt.
There often seems to be concern about powering the UNO in particular, from Vcc or Vin ("barrel jack") whilst connected to USB. Given that the regulated voltages reasonably match - and particularly that there are a polyswitch and a cable of as it turns out, significant resistance between, this would seem most unlikely to cause any problems.
As best as I can determined from the datasheets, applying a voltage which may slightly exceed 5V to the output of the regulator will not cause any problems, apart from a small current loss (approximating its quiescent current draw) through its internal reference.