Hello sirs,
My customer considers the re-start up sequence of TRF7970A in case NFC is in the abnormal condition without any known cause.
The nominal start-up sequence is complied with the sequence described in Figure 6-3 on the TRF7970A's datasheet.
However, in case of the re-start up sequence, VIN keeps high and SS, EN2 and EN are low, and then SS, EN2 and EN are activated.
Regardless of power-down, VIN keeps high by the power in the super capacitor.
Is the above re-start up sequence considered as the appropriate start-up sequence?
Best Regards,
Nomoto