Mifare Series 3-card energy and data transfer

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In the Mifare card, the energy and data are transmitted through the antenna, the antenna in the card is a few turns of the coil, directly connected to the chip, no longer require additional components. The coil is embedded in the plastic and forms a passive contactless card.

Card reader to the IC to send a set of fixed frequency of electromagnetic waves, the card has an IC series resonant circuit, the frequency and reader frequency is the same, so that generates an electric magnetic resonance, so that there is a charge inside the capacitor, the other end of the capacitor with a unidirectional through the electronic pump, the capacitor inside the charge to another capacitor storage, When the accumulated charge reaches 2V, the power supply can be used as the power supply for other circuits to supply the operating voltage, the data of the card is sent out or received by the reader.

A protective layer is generally encapsulated outside the microchip on the card. The protective layer prevents the wafer from being folded, twisted, and many other abnormal physical damage to the card. It also prevents the microchip from being exposed to ultraviolet radiation, allowing the card to be used for a long time. However, from the point of view of electrical performance, due to the addition of a protective layer, the IC and the antenna on the card is composed of the frequency of the oscillation circuit will be changed. Because the protective layer adds an input loop capacitance cmount to the IC microchip. Although the capacitance is only a few pf to dozens of PF, it is also important for contactless IC smart RF cards that require high frequency accuracy and stability.

anti-collision: The intelligent anti-collision function can simultaneously operate multiple cards within the read and write range. The anti-collision algorithm selects each card individually to ensure that transactions with the selected card do not cause data conflicts with other cards in the read and write range.

Ease of Use: Mifare is optimized for the convenience of the user. For example, high-speed data transfer allows complete ticketing transactions to be processed in less than a few Ms. Therefore, the user does not have to stay at the reader antenna, forming a high pass rate, reducing the bus boarding time. When trading, Mifare cards can be left in the wallet, even coins in the wallet are unaffected.

Security: The focus of security is fraud prevention. Mutual random number and answer authentication, data encryption and message discrimination checks and prevention of various cracking and tampering, making it more suitable for ticketing applications. The non-changing serial number guarantees the uniqueness of each card.

Multi-application features: Mifare offers true multi-application capabilities that can be compared to CPU cards. Two different keys per zone support a system with a tiered key.

Mifare Series 3-card Energy and data transfer (RPM)