SST38VF6401 datasheet(21/64 Pages) MICROCHIP

21 / 64 page

DS-20005015B

08/15

64 Mbit (x16) Advanced Multi-Purpose Flash Plus

SST38VF6401 / SST38VF6402 / SST38VF6403 / SST38VF6404

Not Recommended for New Designs

The password can be read using the Password Read command to verify the desired password has

been programmed. Microchip recommends testing the password before permanently choosing Pass-

word Mode.

To test the password, do the following:

Enter the Global Lock of NVPBs mode.

Set the Global Lock Bit to ‘0’, and verify the value.

Exit the Global Lock of NVPBs mode.

Enter the Password Commands mode.

Submit the 64-bit password with the Submit Password command.

Wait 2 µs for the device to verify the password.

Exit the Password Commands mode.

Re-enter the Global Lock of NVPBs mode

Read the Global Lock Bit with the Global Lock Bit Status Read command. The Global

Lock bit should now be ‘1’.

After verifying the password, program the DQ2 and DQ1 OTP bits of the PSR to explicitly choose Pass-

word mode. Once the Password mode has been selected, the Password Read and Password Program

commands are permanently disabled. There is no longer any method for reading or modifying the

password. In addition, Microchip is unable to read or modify the password. If a Password Read com-

mand is issued while in Password mode, the data presented for each word of the password is FFFFh.

If the Password Mode is not explicitly chosen in the PSR, then the password can still be read and mod-

ified. Therefore, Microchip strongly recommends that users explicitly choose Password Mode in the

PSR.

SST38VF6401 Datasheet(PDF) 21 Page - Microchip Technology