Rezence (wireless charging standard)


Rezence is an interface standard developed by the Alliance for Wireless Power for wireless electrical power transfer based on the principles of magnetic resonance. The Rezence system consists of a single power transmitter unit and one or more power receiver units. The interface standard supports power transfer up to 50 watts, at distances up to 5 centimeters. The power transmission frequency is 6.78 MHz, and up to eight devices can be powered from a single PTU depending on transmitter and receiver geometry and power levels. A Bluetooth Smart link is defined in the A4WP system intended for control of power levels, identification of valid loads and protection of non-compliant devices.
The A4WP was formed in early 2012 with the intent to create a wireless power transfer standard to compete with the existing Qi standard. Board member companies include Broadcom, Gill Electronics, Integrated Device Technology, Intel, Qualcomm, Samsung Electronics, Samsung Electro-Mechanics, and WiTricity.
In January 2015 A4WP and the Power Matters Alliance announced that the two organizations intended to merge into AirFuel Alliance.