SLAA502A July   2011  – September 2023 MSP430FR5720 , MSP430FR5721 , MSP430FR5722 , MSP430FR5723 , MSP430FR5724 , MSP430FR5725 , MSP430FR5726 , MSP430FR5727 , MSP430FR5728 , MSP430FR5729 , MSP430FR5730 , MSP430FR5731 , MSP430FR5732 , MSP430FR5733 , MSP430FR5734 , MSP430FR5735 , MSP430FR5736 , MSP430FR5737 , MSP430FR5738 , MSP430FR5739

 

  1.   1
  2.   Low-Power FRAM Microcontrollers and Their Applications
  3. 1What is FRAM?
  4. 2Why FRAM? – An Application Example
    1. 2.1 FRAM: A Universal Memory
    2. 2.2 Write Endurance
    3. 2.3 Fast Write
  5. 3Another Application Example: Light Switch
  6. 4Other Applications
  7. 5MSP430FR57xx Family
  8. 6Conclusion
  9. 7References
  10. 8Revision History

2.3 Fast Write

An additional benefit of the FRAM technology is its fast write capability. To write Flash, tens of microseconds to several milliseconds are required to program one data word (for example, the MSP430F5438A data sheet specifies between 37 µs and 85 µs to program one word, depending on programming mode and process conditions; for other microcontrollers, programming times in the range of 3 to 5 milliseconds are sometimes specified). This does not include a pre-erasure of the segment to be re-programmed. The pre-erasure will add several milliseconds. In addition, no program execution is usually possible while programming.

In contrast, FRAM requires only ~100 ns to program one data word. Additionally, no pre-erase is required and, because of the fast write, there is virtually no interruption of the program execution.