Device Electronic Signature - ST STM32L4x6 Reference Manual

RM0351
45

Device electronic signature

The device electronic signature is stored in the System memory area of the Flash memory
module, and can be read using the debug interface or by the CPU. It contains factory-
programmed identification and calibration data that allow the user firmware or other external
devices to automatically match to the characteristics of the STM32L4x6 microcontroller.
45.1 Unique device ID register (96 bits)
The unique device identifier is ideally suited:
•
for use as serial numbers (for example USB string serial numbers or other end
applications)
•
for use as part of the security keys in order to increase the security of code in Flash
memory while using and combining this unique ID with software cryptographic
primitives and protocols before programming the internal Flash memory
•
to activate secure boot processes, etc.
The 96-bit unique device identifier provides a reference number which is unique for any
device and in any context. These bits cannot be altered by the user.
Base address: 0x1FFF 7590
Address offset: 0x00
Read only = 0xXXXX XXXX where X is factory-programmed
31 30 29 28
r r r r
15 14 13 12
r r r r
Bits 31:0 UID[31:0]: X and Y coordinates on the wafer
27 26 25 24
UID[31:16]
r r r r
11 10 9 8
r r r r
DocID024597 Rev 3
23 22 21
r r r
7 6 5
UID[15:0]
r r r
Device electronic signature
20 19 18 17
r r r r
4 3 2 1
r r r r
1679/1693
16
r
0
r
1681