Near field communications (NFC) coil and proximity sensor for portable devices

摘要

Described herein are techniques related to near field coupling and proximity sensing operations. For example, a proximity sensor uses a coil antenna that is utilized for near field communications (NFC) functions. The proximity sensor may be integrated into an NFC module to form a single module.

主权项

1. A portable electronic device, comprising:
near field communications (NFC) circuitry adapted to process NFC electrical signals from a loop antenna having at least first and second loop antenna terminals; proximity sensing circuitry adapted to process proximity sensing electrical signals from the loop antenna; a low pass filter adapted to substantially isolate the proximity sensing electrical signals from the NFC electrical signals, wherein the low pass filter comprises at least one passive device coupled in series between the proximity sensing circuitry and the first loop antenna terminal; and a high pass filter adapted to substantially isolate the NFC electrical signals from the proximity sensing electrical signals.