AnsweredAssumed Answered

PN532 Antenna Test  

Question asked by Rodrigo Lorenzo Leal on Jun 27, 2018
Latest reply on Jul 5, 2018 by IvanRuiz

Hi NXP forum.


We have a PN532 based product, and some of our units have been having troubles in the field. We have reasons to believe that this is due to poor antenna connection (our contact is not the most reliable). 


We've implemented an antenna self test based on the user manual, but it has been hit or miss. It properly detects when the antenna is detached, but some times gives false negatives when re attached.


After reading the datasheet, we found that it says that this antenna test should only work for VBAT> 5 V, but in our design VBAT = 3.3 V. Is there a way to configure the self test to work with lower voltages?


Additionally, in the user manual says that a register value different from 0x00 means that the antenna is not detected, but in the datasheet it says that the only important bits are 7 and 6. Should I mask the result of the Diagnose command?


Kind regards.