Re: Macbook Pro 85W power adapter?

In article <h697m3$sf5$1@xxxxxxxxxxxxxxxxxxxxxxxxxx>,
Mike <mikee@xxxxxxxxxxxx> wrote:

I have a question about the power adapter (wall wart) for the Macbook Pro
(the 85 watt version if that makes a difference). Is the power adapter
a transformer or a switching power supply? My guess is transformer. I'm
asking to get someone more knowledgeable than me to confirm or deny
my guess.

All Apple wall wart power adaptors are switch mode power supplies. Apple
have never used a transformer style linear power supply, not even in the
Apple II days (however I am not sure about the Apple 1 power supply).

Easy rule of thumb. If the gadget feels hefty like it is made entirely
of iron and copper, it is a transformer. If it feels too light for that,
it is switching.

Another rule of thumb. If the power supply accepts a wide range of input
voltages without flipping a switch setting, then it is a switch mode.
Apple power supplies are usually fine from 90 volts to 250 volts.

--
http://www.ericlindsay.com
.

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