I have noticed the NFC tag sticker antenna's are quite small. Yet when I design and antenna using eDesignSuite it produces solution which are very large.

[SClif.1]

i am trying to design an application using ST25DV04K part. I am having trouble getting an antenna small enough to fit on my board. How do i make a small NFC antenna?

[Denis ROMAN · Accepted solution]

​Hello,

In order to get a small antenna you have to increase the number of turns of the antenna, reduce copper width.

Ultimately, you can use design an antenna etched on both side of the PCB but eDesign Suite does not allow this.

Have a nice day

Denis 

[SClif.1]

Denis,

After working with eDesign Suite i found it has a bug in it. When you put in values they must have a leading zero in front of the number (For example it must be 0.2 not .2) So when you say add more turns it does not calculate properly if the zero is not leading. Second there is an application note that does explain how to use eDesign Suite to make a double sided antenna. This application note is AN5605, as a matter a fact i was able to use it and duplicate the same number of turns you have in a demo board ST offers for sale that has a 14mm square antenna.

Regards

Scott

[Henry Crane]

Hello Scott

thanks for reporting us the leading 0 need. This inconvenience is known and this is something we will address if we have a major upgrade of the software to perform.

Feel free to share if you have comments on AN5605.

Best regards,

Henry Crane RFID/NFC support