Mifare Series 3-card energy source and Data Transmission

In the Mifare card, energy and data are transmitted through an antenna. The antenna in the card contains several turns of coils and is directly connected to the chip without additional components. The coil is embedded in plastic to form a passive non-contact card.

 

The card reader sends a set of Fixed-frequency electromagnetic waves to the IC. The card contains an IC series resonance circuit, which is the same as the frequency of the reader. In this way, magnetic resonance is generated, in this way, the capacitor has a charge. At the other end of the capacitor, a one-way electronic pump is connected to send the charge in the capacitor to another capacitor for storage, when the accumulated storage charge reaches 2 V, this power supply can be used as a power supply to provide the operating voltage for other circuits, transmitting the data in the card or receiving the reader's data.

A protective layer is typically encapsulated on the outside of the microcrystalline film on the card. The protective layer can prevent the microcrystalline film from being folded, distorted, and many other non-normal physical damages to the card. At the same time, it also prevents the microcrystalline film from ultraviolet radiation, so that the card can be used for a long time. However, from the perspective of electrical performance, due to the addition of a protective layer, the frequency of the oscillating loop consisting of the IC and the antenna on the card will change. Because the protective layer adds an input loop capacitor cmount to the IC microcrystalline. Although this capacitor only has a few PF to dozens of PF, it will also be very important for non-contact IC intelligent RF cards that require high frequency accuracy and stability.

 

Conflict prevention:The smart anti-conflict function allows you to simultaneously operate multiple cards within the read/write range. The anti-conflict algorithm selects each card one by one to ensure that transactions are performed with the selected card, without causing data conflicts with other cards in the read/write range.

User convenience:Mifare is optimized for user convenience. For example, high-speed data transmission makes the complete ticket transaction processed within less than 100 ms. Therefore, the user does not have to stay at the reader antenna to form a high pass rate, reducing the boarding time of the bus. During transactions, Mifare cards can be left in the wallet, and even coins in the wallet are not affected.

Security:Security focuses on fraud prevention. Mutual random number and response authentication, data encryption, and packet authentication checks and prevents various cracking and tampering, making it more suitable for ticket applications. The unchangeable serial number ensures the uniqueness of each card.

Multiple application features:Mifare provides real multi-application functions comparable to CPU cards. Two different keys in each zone support hierarchical keys.

Mifare Series 3-card energy source and Data Transmission