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TRF7970A: The TRF7970A's modulation format in ISO/IEC 14443 B

Nomo
Guru 16800 points
Part Number: TRF7970A


Hello,

Could you tell us the TRF7970A's modulation format in ISO/IEC 14443 B?
As the standard of ISO/IEC 14443 B, our understanding is that from TRF7970A to card/tag should be ASK and from card/tag to TRF7970A should be BPSK.
However, we cannot find the term of "BPSK" in the datasheet.

Best Regards,
Nomo

  • 0
    TI__Mastermind 18265 points

    Hello Nomo,

    your understanding of the ISO14443B is correct.

    The reader to tag modulation is 10% ASK. The tag to reader modulation uses a 847kHz subcarrier which is load modulated on the carrier frequency. This subcarrier is BPSK modulated.

    The term BPSK is missing in the datasheet but BPSK demodulation is implicit when selecting ISO14443B in the control register. One hint is given when looking in the block diagram at page 3 which shows for the receiver path a Phase and Amplitude Detector. This will do the BPSK demodulation.

    Best regards,

    Helfried

  • 0 in reply to Helfried Vollbrecht
    Guru 16800 points

    Hello Helfried-san,

    Thank you for your prompt support.

    I could understand the specification of TRF7970A for ISO14443B.

    Best Regards,

    Nomo