The working voltage of FM24W256 is from 2.7V to 5.5V. Five numbers are saved to FRAM when voltage < 3V. From the time "<3V" is detected to the time data is saved in FRAM, the voltage is varying since I2C module also needs a little time to transfer data. I guess FM24W256 may fail to work since the voltage might below 2.7V. How about using MSP430FRxxxx to replace MSP430F67791 +FRAM?
↧