So I have made a project and want to deploy the arduino permanently but want another one to play with and use for future projects. Should I deploy the Duemilanove w/Atmega328 that I have or should I order some sort of stripped down version that is cheaper. I’m not even sure if there is such a thing.
This is what I’ve been using…
I like making stripboard Arduinos. Probably the cheapest way of deploying an Arduino
Thanks for all the suggestions. So far I like http://www.moderndevice.com/products/rbbb-kit the best given my experience level. Can I program the ATmega328 chip by swapping it out in my Arduino? What’s the cheapest wall power supply that I might be able to pick up locally in the US?
yea you can swap chips, far as wallwarts go, depends on what you need (and I dont really know I havent bought a power adapter in years, i have a small box of them of different sizes collected over the years from dead phone machines and ect)
From what I read about that particular voltage regulator it will accept 5 to 12 volts. If I attach the right power jack (2.1mm, center terminal positive) can I use any 5 to 12 volt power supply I have laying around?
How much current do you draw from the power supply? The higher the input voltage
you use the more power you dissipate in the voltage regulator and the hotter it runs.
Running the device hotter decreases the reliability.
(* jcl *)
Should I try to find one with a low current draw like 1A?
The current drawn from the power supply is determined by your Arduino + peripherals not from the power supply. Reducing the maximum power supply current will not affect the power dissipated in the regulator. Reducing the power supply voltage will. IIRC the Arduino specs a voltage of 7V minimum. Any voltage above 7V is unnecessary.
Using a power supply with a lower maximum current does have a couple of benefits —
- Power supplies are usually most efficient at currents between 75%-100%
of the specified maximums. If you are using a power supply well below
the maximum you are wasting energy.
- If there is a fault in your circuitry having a lower maximum current may
help limit the damage. This depends on how the power supply
was designed to deal with faults.
(* jcl *)
Can you explain what’s happening when you hook a 9v battery up to it? What current does a 9v battery supply anyway?
batteries will push quite a bit of current, for a little bit anyway … a 9v can hold about 500ma for roughly an hour
the 7805 will actually handle more than 12 volts, but it has to dissipate the extra power by heating up
I run mine all the time on a 12v 1 amp brick, but I also have a heat sink on my regulator and it still gets warm quickly (2-300 ma) but not hot hot hot (and it’s a crappy heat sink anyway, just the best i could fit on the bare bones board)
Also that RBBB does not have a 7805, it comes with something else which is much smaller in the ratings department, you can replace it with a 7805, slap a heat sink on it and get away with a 12v power source (exact amperage would depend on cooling)
And of course, what you choose to power it with depends on what your trying to power along with the arduino
The capacity of a battery is typically expressed in mAh or Ah.
You can draw a specified amount of current for a specified amount
of time after which the battery voltage is at a specified voltage level.
The battery capacity will change depending on the amount of current
you draw. Typically you get a higher capacity at lower current levels.
For example a 9V battery (Energizer 522) has a capacity of 600mAh when
you draw currents of 25mA. The capacity drops to 300mAh when drawing
500mA. After the capacity is exceeded the battery voltage of the 522 is
If your application could run at a voltage level of 4.8V (which an Arduino with a regulator won’t) you would get 24 hours of operation at a 25mA load and
0.6 hours at 500mA.
There is an online electronics textbook at allaboutcircuits.com It is an excellent
(* jcl *)