Factory Passcode Key (FPK)

The factory passcode Key (FPK) is a 256-bit unique passkey used to set the device in factory test mode. FPK can override all non-permanent factory-defined locks. The factory test mode allows in-depth testing of the device by Microchip for failure analysis. When a passcode is entered for attempted validation, the entered passcode is hashed, and compared with the hashed version present in the device.

User must enable (as shown in the following figure) the factory test mode access if the user wishes Microchip to perform failure analysis on a given device. The user can permanently disable factory test mode access. When that is done, no future failure analysis is possible.

Figure 1. Factory Test Mode Access