A physical switching device for multiplexing an NFC coil and a wireless charging coil

Abstract

A physical switching device for multiplexing NFC coils and wireless charging coils includes a first coil, a second coil, a carrier, a metal circuit, an NFC circuit, a wireless charging circuit, a first physical switching mechanism, a second physical switching mechanism and a third physical switching mechanism; during wireless charging, the first physical switching mechanism combines the first coil and the second coil to form a charging coil under the effect of the static magnetic field of an external charger, and the third physical switching mechanism enables the charging coil to communicate with the wireless charging circuit to form a wireless charging loop, and at the same time, the second physical switching mechanism cuts off the NFC circuit; during NFC communication, the first physical switching mechanism disconnects the first coil and the second coil which are combined together, and the third physical switching mechanism disconnects the wireless charging circuit, and the second physical switching mechanism enables the first coil to communicate with the NFC circuit to form an NFC communication loop. The physical switching device for multiplexing NFC coils and wireless charging coils realizes switching between wireless charging and NFC communication physically, so that the disconnection of the circuit is complete without either efficiency loss or signal interference therebetween.

Description

technical field [0001] The invention relates to the technical fields of NFC and wireless charging, in particular to a physical switching device for multiplexing an NFC coil and a wireless charging coil. Background technique [0002] The full name of NFC is Near FieId Communication, that is, near-field communication, which is derived from radio frequency identification (RFID, Radio Frequency Identify Detection) technology. It is a non-contact identification and interconnection technology jointly developed by Sony and Philips to realize Point-to-point short-range communication between various devices. NFC technology is widely used in wireless payment, data transmission and other fields. In recent years, as mobile payment has become more and more popular in life, NFC has gradually become the standard configuration of smartphones. At the same time, the long-silent wireless charging technology has The charging power has been significantly improved, and the space and resources oc...

AI Technical Summary

Problems solved by technology

[0003] However, although NFC and wireless charging reuse the same piece of ferrite electromagnetic shielding material, the coil and circuit exist independently, which will cause a problem: when the given occupied area is certain, the NFC coil and wireless charging coil often need Compromise on area and isolation leads to deterioration of both NFC coil performance and wireless charging coil performance. At the same time, NFC coil and wireless charging coil are inevitably in close contact, and mutual interference cannot be effectively eliminated in a small space. Therefore, , the industry has proposed the idea of ​​sharing a coil with NFC and wireless charging

[0004] At present, NFC and wireless charging coils realize time-division multiplexing of NFC and wireless charging coils in the form of electronic switches. However, the electronic switch implementation method has the following disadvantages: 1. Electronic switches generally cannot withstand large power, and the wireless charging power is as high as Above 10W, it is necessary to develop an electronic switch with a larger rated power; 2. The electronic switch is not completely turned off, resulting in poor isolation between the NFC and the wireless charging coil, and large signal crosstalk; 3. The introduction of the electronic switch will inevitably cause efficiency The drop in temperature will be converted into excess heat, which poses a challenge to the heat treatment of mobile terminals

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