TDK Corp developed what it claims is the industry's thinnest power-receiving coil unit for the wireless power transmission for smartphones.
The thickness of the unit is 0.57mm. The company will start production of the coil unit at its manufacturing plant in Taiwan in the second half of 2012 at a monthly production rate of 500,000 units.
The power-receiving coil unit consists of a coil made of copper (Cu) and a metal magnetic sheet. In 2011, TDK started to ship a 0.9mm-thick power-receiving coil unit. This time, the company realized the thickness of 0.57mm mainly by reducing the thickness of the magnetic sheet. Also, by using the metal magnetic sheet, it ensured an impact resistance required for use with smartphones.
The new power-receiving coil unit meets the transmission efficiency standards required for the "Qi" standard established by Wireless Power Consortium (WPC), an industry group for wireless power transmission, TDK said. It supports an output current of about 0.5-0.6A. The company expects that the unit will be used not only for smartphones but for digital cameras and Bluetooth-compatible headsets.
For the future, TDK plans to develop a power-receiving coil unit whose thickness is 0.50mm and start to mass-produce it in 2013.