The RF reader sends a set of electromagnetic waves with fixed frequency to the ic card, and there is an IC series resonant circuit in the card, the frequency of which is the same as the frequency sent by the reader, so that the LC resonant circuit resonates under the excitation of electromagnetic waves and charges the capacitor;

At the other end of this charge, a unidirectional electronic pump 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, send data in the card or receive data from the card reader.

Extended data

Advantages of IC card:

1, safe

The security of IC card is far greater than that of ID card. The card number in the ID card can be read without any authority, so it is easy to copy. The reading and writing of the data recorded in the IC card requires corresponding password authentication, and even each area in the card has different password protection, which fully guarantees the data security. The passwords for writing data and reading data in IC card can be set differently, which provides a good hierarchical management method and ensures the security of the system.

2. Recordability

The ID card can't write data, and its record content (card number) can only be written once by the chip manufacturer. The developer can only read the card number and use it, and it is impossible to formulate a new number management system according to the actual needs of the system.

IC card can not only be read by authorized users, but also be written with a large amount of data (such as new card number, user rights, user data, etc.). ) by authorized users, the contents recorded in the IC card can be erased repeatedly.

3. Storage capacity:

ID card only records the card number; An IC card can record about 1000 characters.

Baidu encyclopedia -IC card