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AC/DC laptop power supply

  1. Aug 4, 2009 #1
    Just a quick question for you guys out there. I have an AC/DC laptop power supply. I was thinking of using it for a few projects. Th power supply's output is 19 volts and 3.16 amps. My question is is 3.16 amps the max current that the power supply can take without frying? I mean the number of amps in a circuit depends on the voltage and resistance in the circuit. Specifically ohms law (V/R=I). It can't just spit out 19 volts and 3.16 amps on any circuit, right?

    Thanks for your help! :smile:
  2. jcsd
  3. Aug 4, 2009 #2
    It means that it is the maximum current the power supply is rated to output at that voltage.

    If you exceed it, it could shorten the life, or worse, cause it to overheat and start a fire.
  4. Aug 5, 2009 #3
    Thrse "brick" power supplies are usually very well voltage regulated, and if the nameplate current rating is exceeded, will often either shut down completely and need to be unplugged to reset, or go into a powerdown mode and will not supply rated voltage again until the current overload condition is removed. Worst case is that they will overheat and catch fire. Do not exceed current rating.
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