Lc is a hotel.

Let's see if the room card of the hotel room needs a chip to power on. If you don't need it, it's similar to photoelectric induction. Just use any card to block it. If necessary, you can go to the front desk and ask him to give you another one, which is usually given.

Second, the role of the hotel room card:

(1) The room card can control the lights and sockets in the room, and all the lights and sockets in the room will not work unless they are plugged into the socket, so the room card is equivalent to a switch on the road.

(2) When the lamp plug of the disconnector is plugged into the socket, all other lamps in the room are extinguished.

Third, the hotel or hotel room card has a high safety factor and is more convenient to use. The basic principle of the room card is that the RF reader sends a set of electromagnetic waves with a fixed frequency to the room card, and there is an LC series resonant circuit in the card, the frequency of which is the same as the frequency sent by the reader, so that under the excitation of electromagnetic waves, the LC resonant circuit generates * * * vibration to charge the capacitor; At the other end of the capacitor, an electronic pump with unidirectional conduction is connected to send the charge in the capacitor to another capacitor for storage. When the accumulated charge reaches 2V, this capacitor can be used as a power supply to provide working voltage for other circuits, and transmit data in the card or receive data from the card reader.