NFC waveform pattern during communication

[kiranym]

Hi,

Could you help us to know the expected NFC waveform patten (modulation, how we can identify data (0 and 1s)) when reader (ST25R3916B) and tag (ST25DV04KC) communicate each other please? Please share some example waveforms so that we can understand and check/verify in our design.

Thank you,

Kiran

[Ulysses HERNIOSUS]

Hi Kiran,

Coding etc. are described in ISO/IEC 15693-2/3 or NFCForum Digital spec. 

Best to compare waveforms of one of our designs against your design when sending the same frame. I can recommend:

1. Oscilloscope: Create a loop by connecting the ground cable to the tip.
2. Digital analyzer using observation modes tana=0xB (for receiving) and potentially tana=0xA (for sending) - observing TAD1/TAD2.

BR, Ulysses

[kiranym]

Hi Ulysses,

Thank you, for the help. Could you recommend instrument model for monitoring the waveforms please?

Thank you,

Kiran

[Ulysses HERNIOSUS · Accepted solution]

Hi Kiran,

I cannot make specific recommendations. I am using often a PC attached mixed signal oscilloscope:

• 200 MHz analog bandwidth
• 1 GS/s real-time sampling
• 512 MS buffer memory
• 100,000 waveforms per second
• 16 channel logic analyzer
• Protocol analyzer (SPI)

For debugging my software I prefer Logic analyzers which can decode SPI and are much better in navigating and filtering than the scope. I have seen a plethora of analyzers being used. Personally I am most of the time on either Digiview or Saleae (>= 8 channels).

BR, Ulysses

[kiranym]

Hi Ulysses, OK. Thank you, for the help. Thank you, Kiran