The ID card mentioned here refers to the second-generation resident ID card that we usually use, after all, the third-generation ID card is still the concept stage.
Here can be very clear to tell you that the second generation of resident ID card and mobile phone together will not be demagnetized, even if your mobile phone has NFC, headphone speaker magnets and other effects will not bring demagnetization to the ID card.
The reason is still very simple, the second generation of resident identity card uses contactless IC technology, that is, RFID (radio frequency identification) technology.
We can use the mobile phone fill light and small flashlight to illuminate the ID card at close range, and we can see the RFID electronic tag chip part and the antenna part.
ID card information is stored in a chip, rather than the old-fashioned magnetic stripe bank card storage method.
When reading the internal information of the second-generation resident ID card, the reading device emits a fixed frequency, which will be charged through the capacitor in the ID card circuit, and the voltage will reach 2V, and the chip information can be read, so that data interaction can be carried out.
Therefore, there is no such thing as "demagnetization" for id cards.
In ordinary life, some people's second-generation resident identity cards are damaged, although some people often say that the identity cards are "demagnetized", in fact, this is not the case. It is very likely that the ID card has been physically damaged, the internal antenna, chip and other small components have contact disconnection, or there is direct physical damage. It is also possible that static electricity and large currents can damage internal components.
The power of the mobile phone will not form an electromagnetic induction that damages the ultra-large current of the internal circuit of the ID card, so it is impossible to demagnetize the mobile phone and the ID card together.
Not only that, the chip is inside the card, if it is not super static electricity, it will not damage the internal circuit of the ID card.
However, some people like to put the ID card on the mobile phone case, especially the kind of card package, sometimes disassembling the mobile phone case will be deformed, which will often cause the ID card to bend, which is possible to damage the internal components.