AN13321: TPMS FLASH Protection and Security
Application note detailing FLASH block protection and security implementation for NXP FXTH87 and NTM88 tire pressure monitoring systems (TPMS).
Overview
This application note describes how to implement and manage FLASH memory protection and security features for NXP FXTH87, FXTH87E, and NTM88 tire pressure monitoring system (TPMS) devices. It covers the FLASH Memory Controller's ability to prevent unauthorized program or erase operations through block protection, which is critical for maintaining bootloader integrity during Over The Air (OTA) updates. The document also explains security mechanisms that restrict external access to FLASH and RAM via background debug controllers or SPI. Technical details include register configurations for FPROT, NVPROT, FOPT, and NVOPT, as well as procedures for enabling protection at runtime or during production, using backdoor security keys, and handling mass erase operations.
Use Cases
- Protecting bootloader code from accidental erasure during OTA updates
- Securing sensitive sensor data and firmware against unauthorized external access
- Configuring memory protection boundaries in automotive TPMS applications
- Implementing temporary security unlocking for field diagnostics using backdoor keys
Topics
Referenced Parts
FXTH87
NXP
Keywords FXTH87, FXTH87E, NTM88, FLASH block protection, security, TPMS
NTM88
NXP
The information provided in this document is compatible with all devices of the FXTH family implementing library-based applications and all devices of the NTM88 family.
| FXTH87E | NXP | Keywords FXTH87, FXTH87E, NTM88, FLASH block protection, security, TPMS |
| FXTH87 | NXP | Keywords FXTH87, FXTH87E, NTM88, FLASH block protection, security, TPMS |
| NTM88 | NXP | The information provided in this document is compatible with all devices of the FXTH family implementing library-based applications and all devices of the NTM88 family. |