Flash Memory Read Endurance

Discussion in 'General Electronics Chat' started by Sensacell, Oct 21, 2012.

  1. Sensacell

    Thread Starter Well-Known Member

    Jun 19, 2012
    I have an application that needs to READ from a 16 Mbit FLASH memory (SST25VF016B) constantly over a long period of time, I have heard that FLASH memory can have read-endurance issues, but I cannot seem to find a clear answer to what this really means in practical terms.

    The data sheet is very clear about WRITE ENDURANCE, listing this as 10,000 cycles, but this is not a problem in my application as there will be very few write cycles.

    I have found some discussions on the web regarding flash memory "read disturbance" but this is never quantified, can anyone shed some light on this?
  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
    The only thing I found is here: http://www.edn.com/electronics-blogs/other/4307057/NAND-Read-Disturb-Shoo-Fly-Don-8217-t-Bother-Me
    How many reads do you perform? If you really need to be sure because of the design, you can make a setup that keeps reading the flash till it loses the data and see how long it takes.
    Also if your devices has stable power supply you can transfer the flash data into RAM on bootup and then read from there. Or refresh the data in flash every now and then.
  3. Sensacell

    Thread Starter Well-Known Member

    Jun 19, 2012
    Thanks for pointing me to that article.

    I need to perform millions of read cycles.

    If the flash memory in a modern micro-controller had this issue, they would all die quickly, as this is exactly what a micro-controller executing a code loop does, it reads from the same memory cells over and over and over...

    Is the flash in a micro typically different from the flash in a high density memory? Designed for density, rather than endurance?