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Apple 20 Watt USB-C Power Adaptor

Why does Apple's 20 Watt USB-C Power Adaptor say its 5V output is 3 amps? Shouldn't 20W/5V=4 amps? I assume I am missing something about Apple's or USB's power protocols.

iPad Air Wi-Fi

Posted on Dec 24, 2022 10:27 AM

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MrHoffman

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Posted on Dec 24, 2022 10:37 AM

fourwheelcycle wrote:

Why does Apple's 20 Watt USB-C Power Adaptor say its 5V output is 3 amps? Shouldn't 20W/5V=4 amps? I assume I am missing something about Apple's or USB's power protocols.

20W can provide a maximum of either 5V3A or 9V2.22A.

Apple USB-C power adapter volts, amps - Apple Community

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Apple 20 Watt USB-C Power Adaptor

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