Smart watches, fitness wristband and headset and other low-power wearable devices have been pushed to the market. It is expected that in the next few years, this new series of electronic products will be the rapid development of the camp. It includes Qi compatible wireless power systems, low power wireless systems. A typical wireless power supply system has a receiver (Rx) in the portable device, which provides the energy to charge the battery. By carefully adjusting the coil size and external component values to match smaller size applications, the low power wireless system can be optimized for existing Qi compatible receivers and transmitters. Both the transmitter and the receiver coil can be reduced in size to fit the smaller shape. Power part of the components (especially for the transmitter) can reduce the power specifications. So better play the advantages of wireless charging. Believe that these products will be more and more in the next few years.