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Moreover, this information can be encrypted by the reader before programming so the data

stored in the tag are useless to anybody else who might be reading it. Most RFID tag ICs

also come with several data protection schemes to help protect their contents.

When it comes to implementation, RFID chips are available from STMicroelectronics in a

soldering-friendly package such as UFDFPN8 (MLP8).

As far as the antenna is concerned, designers would replicate what RFID antenna

designers do. To some extent, the inlay process is a very simple, one-layer, thin-flex PCB

process where the antenna is etched off. STMicroelectronics application note AN2866

provides insight for designing and validating an RFID antenna.

You can design three types of antenna: on-board, off-board and daughterboard antennas.

Antenna types

On-board antennas

Figure 1 shows an on-board antenna example. The pros and cons are then summarized.

Figure 1.

On-board antenna

Pros

●

Integrated and compact solution

●

No connector, better reliability

Cons

●

Less space available on the PCB for a large antenna. Read range may then be smaller

●

More sophisticated PCB design to avoid interference with the RF signal

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