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ADXL350 Abnormal behavior

Hello, I'm Dohwan Kim. I'm a Korean.
Please understand that I am not good at English.

Our company used the ADXL350 to make a Roll Data measuring device. 200 units a year were produced for 3 years, and there are plans to continue production for several years in the future.

The MCU used to read Roll Data is TI's MSP430 series, and the ADXL350 is controlled by SPI communication implemented using the MCU's GPIO.

However, abnormal operation occurs in some of the created devices.

If the power is turned OFF -> ON when the temperature of the device is over 40 °C all registers of ADXL350 are not R/W.

Actually, I don't know if I can write it or not.
A read reads zeros from all registers.
Turn off the device, let it cool down, and then turn it on again to operate normally.

Most devices work normally even after heating to about 70 °C and turning on the power, but a small number of devices behave abnormally.

Abnormal operation cannot be solved with S/W,
and If the power of the ADXL350 is turned on later than the MCU after disconnecting the power of the MCU and the ADXL350, it operates normally even in the presence of heat.
Also, if the ADXL350's power is OFF-ON in the abnormal operation state, it will operate normally.

It seems that the heat problem and the power problem coexist.

I am not sure if it is a problem with the manufacturing process or if the ADXL350 is defective.

If you know anything about this phenomenon, please let me know.

Reference.
The power supply of MCU and ADXL350 shares a 3.3V supply.

A schematic is attached