1 Reply Latest reply on Jun 21, 2018 8:20 PM by scotth_21

    [S25FL127S] protection mode

      part number: S25FL127SABMFV101


      Our board is using S25FL127S flash memory.

      I repeatedly turned the power on and off during the testing process.

      The flash memory is protected by quickly repeating the above process

      Other than flash memory, everything works normally.

      I tried the review, but I could not find the cause.



      1. OK state

      Reg Addr / Data

      0x35 : 02

      0x05 : 00


      2.NG state

      Reg Addr / Data

      0x35 : c2

      0x05 : 9c


      0x35 : Configuration Register 1 (CR1)

      0x05 : Status Register 1 (SR1)


      Is the status of the flash memory normal?

      please tell me why flash memory is protected.


      Thank you.

        • 1. Re: [S25FL127S] protection mode

          Hello HS Jeon,


          it is suspected that the flash device couldn't complete an flash internal initialization process during your power off/on cycles. it leads further array data access or SR/CR have incorrect settings temporarily. You may need to check the power-up/down voltage and timing in below, which also can be seen on S25FL127S datasheet.




          Best regards,