How could a charger "cut out" when charging is complete?

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Why is it so problematic to have close to zero standby power consumption?
How would you detect vampire/standby power?

This article discusses why cell phone users have to unplug the cell phone charger once charging is complete to avoid unnecessary consumption of energy when the charger goes into standby mode and why the charger itself couldn't somehow shut off.

First they explain that ay kind of electrical switch would need some standby power and so zero consumption is impossible. Then they say they

could make a charger that cuts out when the phone is full

but that would require a lot of extra components that complicate charger production and that offsets all the benefits.

What do they mean saying "cuts out" and how can that be implemented?

http://electronics.stackexchange.com/questions/11899/why-is-it-so-problematic-to-have-close-to-zero-standby-power-consumption — Kellenjb, Jan 18 '12 at 14:42
@Kellenjb: That question's answers don't mention "cutting out". — sharptooth, Jan 18 '12 at 14:43
http://electronics.stackexchange.com/questions/13513/how-would-you-detect-vampire-standby-power — Kellenjb, Jan 18 '12 at 14:44

score 1 · Answer 1 · answered Jan 20 '12 at 02:48

It's pretty easy to make a charger that completely switches off any connections to the cell phone, so no more power goes into the cell phone.

However, most such systems still have a small amount of "standby" power trickling through the charger itself.

By "cuts out", I'm pretty sure they mean that (practically) no power comes out of the wall into the charger -- power is cut off to the charger and the cell phone, not just cut off to the cell phone.

The closest I've seen so far to a circuit that completely turns itself off is Roman Black's Zero-power PIC self-switch.

Recently discovered Roman Black's circuit and the one you linked too was brilliant. — efox29, Mar 14 '16 at 21:37

How could a charger "cut out" when charging is complete?

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