hi NXP,
I am Working with NTM88 ic for TPMS while testing (mounted on rim outside the tire ) we observed that the NTM88 ic id change to FF
for example : consider NTM88 ic having it's ID "C927045E" while testing it showing "FFFFFFFF".
Solved! Go to Solution.
Hi Pranav,
What about sensor measurements? Does the chip still gives valid values?
If sensor measurements give invalid values (underflow/overflow status returned), it means the trim section (including the unique ID) has been erased.
In your application, have you implemented functions to reprogram the flash? Are you calling TPMS_FLASH_WRITE or TPMS_FLASH_ERASE?
This happens if a reset occurs while address 0xFFBF is erased (0xFF value). During programming, care must be taken not to have glitches on the VDD or RESET line in order to avoid a reset between the moment address 0xFFBF is erased and the moment it is written again.
For more information on chip security, please refer to below application note:
https://www.nxp.com/docs/en/application-note/AN13321.pdf
BR, Tomas
Hi Pranav,
I have not heard about such an issue before, could you please share more details about your test conditions and the number of NTM88 ICs tested? I have also forwarded your question to our TPMS SW engineer and will get back to you as soon as I have her answer, likely next Monday as she is out of the office this week.
BR, Tomas
Hi Pranav,
What about sensor measurements? Does the chip still gives valid values?
If sensor measurements give invalid values (underflow/overflow status returned), it means the trim section (including the unique ID) has been erased.
In your application, have you implemented functions to reprogram the flash? Are you calling TPMS_FLASH_WRITE or TPMS_FLASH_ERASE?
This happens if a reset occurs while address 0xFFBF is erased (0xFF value). During programming, care must be taken not to have glitches on the VDD or RESET line in order to avoid a reset between the moment address 0xFFBF is erased and the moment it is written again.
For more information on chip security, please refer to below application note:
https://www.nxp.com/docs/en/application-note/AN13321.pdf
BR, Tomas