Würth Elektronik eiSos GmbH & Co. KG has introduced new wireless power coils for wearables. Since devices such as fitness sensors and smart watches are generally encapsulated to protect them from the effects of the environment, but also have to be recharged frequently, the contactless transfer of energy without a charging plug is growing more popular.
The main feature of the WE-WPCC 760308102212 and WE-WPCC 760308102213 receiver coils is their extreme thinness of just 0.64 mm, making them suitable for use in wearables with space for relatively large coil areas (29 x 29 mm), but with strong limitations regarding their height. In addition, the broad ferrite projection of the WE-WPCC 760308102212 unit has excellent shielding properties - an important aspect in applications that are sensitive to electromagnetic interference.
The selection of the inductance value used in the WE-WPCC 760308102213 product makes it a dual-standard receiver. Fitted with the corresponding receiver chip, the coil is capable of responding to transmitters that are compatible with either the WPC Qi standard or the PMA standard. The third receiver coil, the WE-WPCC 760308101214 product, is slightly thicker at 0.8mm, a feature that is offset somewhat by having a diameter of just 19 mm.
To make charging stations that are ideally compatible with these receiver coils, Würth Elektronik eiSos also offers two new wireless power-charging transmitter coils, the WE-WPCC 760308101104 and WE-WPCC 760308101105 products. Both coils have an external diameter of just 21 mm, and use high-quality ferrite for shielding and stranded wire to keep the RDC to a mini-mum. The two coils differ in their inductance values.