Is NFC a battery drain at all?

Steve686

macrumors 68040
Original poster
Nov 13, 2007
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Not sure if NFC is a battery drain for those who do not want to use it. I know you can use it even when the screen is locked, and I loved that feature. Makes it absolutely flawless.

I assume it's a very, very low output signal, hence, Near Field...

But, is there also a way to turn it off? And does Airplane Mode turn it off?(Forgot to check this when I did a couple of :apple:Pay transactions earlier today.
 

Intell

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Jan 24, 2010
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It is only turned on and used when preforming a non-in app Apple Pay transaction. At all other times, it is turned off. Even when on, it uses very little power.
 

Steve686

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Nov 13, 2007
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It is only turned on and used when preforming a non-in app Apple Pay transaction. At all other times, it is turned off. Even when on, it uses very little power.
But how is it activated from lock screen, then? There has to be a signal that wakes the NFC radio? But in order to do that, wouldn't the NFC radio already be required to be on/receiving?

I know it uses very little power, I just want to know exactly what activates Apple's particular NFC modes.
 

Intell

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Jan 24, 2010
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Don't forget that NFC is also passive in nature. It will and can receive a wake up signal without needing any power. It will only transmit once a transaction is taking place. All while using such a small amount of power it isn't even worth comprehending.