NFC FPC Antenna Thickness and Track Length

[Ignacio]

Hi there,

A couple of questions about the NFC FPC antenna that comes with the nRF52 dev kit.

As indicated on the Altium PCB file, the thickness of the stiff area (connector) is 0.3mm. What's the thickness of the rest of the antenna?

If  I would like to use the same antenna design but lengthen the connecting wires. Shall I just extend the same crossing pattern? The length between crossings is longer the further from the antenna, is it any specific RF design rule to follow there?

Thanks

[Kaja]

Hi, 

I will get back to you tomorrow. 

Best regards,
Kaja

[Kaja]

Hi,

sorry for the delayed answer! 

So our NFC antenna is printed on a flexi pcb, here is the layer stack:


so the thickness of the pcb: 0.142 mm. 

If  I would like to use the same antenna design but lengthen the connecting wires. Shall I just extend the same crossing pattern? The length between crossings is longer the further from the antenna, is it any specific RF design rule to follow there?

 So the use of the crossing pattern is just to make the antenna more rebuts for interference, you can extend the crossing pattern or not, depending on if you have three layers to use all the way to the chip. 

Best regards,
Kaja