How you ever wondered why the Apple iPhone AC charger block is so small l and so expensive? I did, and found a blog that tears it down and reveals the amount of engineering that went into just the AC charger block.
Take a look:
http://www.righto.com/2012/05/apple-iphone-charger-teardown-quality.htmlDisassembling Apple's diminutive inch-cube iPhone charger reveals a technologically advanced flyback switching power supply that goes beyond the typical charger. It simply takes AC input (anything between 100 and 240 volts) and produce 5 watts of smooth 5 volt power, but the circuit to do this is surprisingly complex and innovative.
Wow! I had no idea!