The 2450AT42E010xx chip antenna is unique in that it must have metal directly underneath on the bottom layer of the PCB it is mounted in order to function properly. The antenna was specifically designed for small coin cell, wearable, IoT and related short range applications where metal or a battery/display covers the entire length or side of the PCB or encasement under the antenna and there is no room for the usual/typical antenna metal clearance requirements. Please submit any questions at this link.
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