Integrated Device Technology has released what is said to be the world’s smallest 2W contactless-charging power receiver chip. In the future when all our internet-connected portable and wearable devices need a recharge after a busy day with their head in the cloud, contactless charging will be the way to go. The IDTP9026 wireless-charging receiver chip has a board footprint of just 30 square millimetres and is designed to charge a standard lithium-ion battery rated at 4.2 V. An AD pin allows the device to be switched out of the charging circuit when an external adapter is used for recharging. A separate enable pin is also available to turn the device off.
For more detail: Receiver Chip for Wireless-Charging
French 
English