Other Parts Discussed in Thread: MSP-TS430RGZ48C
I'm having a problem with the SRAM area of the MSP430FR5964IRGZR that my customer is using.
This is the same customer and the same device as the previous case supported in the following thread. In that case, the problem was that 0 was written to some areas of the FRAM, but this time the problem is that 1 is written to some areas of the SRAM.
Should I ask TI to analyze the problem as in the above thread?
I tested with the following method.
- Put the faulty MSP430FR5964IRGZR on MSP-TS430RGZ48C and leave it in a thermostatic bath at -20°C for about 2 hours.
- Turn on the power and write 0xFF to the SRAM area. Then, copy the contents of the SRAM area to the FRAM area. Then, compare 0xFF with the contents of the SRAM area, and if they do not match, an error is judged.
- Write 0x00 to the SRAM area. Then, copy the contents of the SRAM area to the FRAM area. Then, compare 0x00 with the contents of the SRAM area, and if they do not match, an error judgment is made.
- An error occurs in No. 3, and when we checked the contents of the FRAM, we found that 1 was irregularly written to bit 6. (0x40 is read out).
I have attached the verification program and an excerpt of the verification result.xlsx.
Is this problem expected to be the same reason as the above thread?
I will summarize the information below.
- The SRAM area used is 0x2082~0x3540. The area where a 1 appears on bit6 looks like 0x2802~0x2BFF.
- The FRAM area used is 0x4000~0x54BF.
- This problem cannot be confirmed at normal temperature, but it is reproduced -100% in the environment below -20°C.
However, when the temperature is raised from the error state at -20°C to room temperature and read again, normal values are read out.
- This problem has occurred in 2 out of 4000 units.One of them includes the previous FRAM failure, so it is actually one unit.
As for the normal product, it works even at -20°C in the same test.
- Cross-checking was performed, but the problem is still with the IC.
Good IC + defective board = no error
Defective IC + good board = problem occurred
Defective IC + MSP-TS430RGZ48C = Problem occurred.
- The Revision # of the device is "C".
- The manufacturing lot is different from the previous lot by about half a year.
If there is anything else I should check, please let me know.