SLAZ099AA October 2012 – May 2021 CC430F6126
PMM Module
Functional
Vcore exceed maximum limit of 2.0V.
If the device is switching between active mode and LPM2/3/4 with very high frequency, the core voltage of the device, VCORE, may rise incrementally until it is beyond 2.0 V, which is the maximum allowable limit for digital circuitry internal to the MSP430. This increase may remain undetected in an application with no functional impact but could potentially result in decreased endurance and increased wear over the lifetime of the device, because the digital circuitry is continually subjected to overvoltage.
The accumulation of Vcore affects only older lot trace codes of mentioned revisions.
The VCORE accumulation is fixed by enabling the prolongation mechanism in software. The following lines of code need to be implemented before periodic execution of LPM-to-AM-LPM. It is recommended to execute the code at program start:
ASM code:
mov.w #0x9602, &0110h;
bis.w #0x0800, &0112h;
C code:
*(unsigned int*)(0x0110)=0x9602;
*(unsigned int*)(0x0112)|=0x0800;
The automatic prolongation mechanism is disabled with a BOR and must be enabled after each boot code execution.
For detailed background information, affected LTCs and possible workaround(s) see Vcore Accumulation documentation in SLAA505.