in regards to power adapters, mainly the brick-type ones that come with laptops and external hard drives, how is the output current greater than the input current?(adsbygoogle = window.adsbygoogle || []).push({});

for example, i see a laptop power brick with the following:

input 100-240V~1.7A 50-60Hz

output 18.5V == 3.5A 65W

how exactly does this work with a branch current method of analysis if the branch going into the power brick is 1.7A? i see that you can pull current from voltages, but if only 1.7A is going into the network, where are the other carriers coming from to bump up the output to 3.5A?

i've been trying to think this out but i can't arrive at anything. what i left off on is that 1 ampere = 1 coulomb per second. if the input is 1.7A = 1.7 coulomb per second operating at 50-60Hz, perhaps it actually collects enough current to drive 3.5A?

i'm a bit lost.

thanks!

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# AC/DC Power Adapters: Input & Output Specifications

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