53. 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 STM32L552xx and STM32L562xx microcontrollers.
53.1 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: 0x0BFA 0590
Address offset: 0x00
Read only = 0xXXXX XXXX where X is factory-programmed
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
| UID[31:16] | |||||||||||||||
| r | r | r | r | r | r | r | r | r | r | r | r | r | r | r | r |
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| UID[15:0] | |||||||||||||||
| r | r | r | r | r | r | r | r | r | r | r | r | r | r | r | r |
Bits 31:0 UID[31:0] : X and Y coordinates on the wafer
Address offset: 0x04
Read only = 0xXXXX XXXX where X is factory-programmed
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UID[63:48] | |||||||||||||||
| r | r | r | r | r | r | r | r | r | r | r | r | r | r | r | r |
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| UID[47:32] | |||||||||||||||
| r | r | r | r | r | r | r | r | r | r | r | r | r | r | r | r |
Bits 31:8 UID[63:40] : LOT_NUM[23:0]
Lot number (ASCII encoded)
Bits 7:0 UID[39:32] : WAF_NUM[7:0]
Wafer number (8-bit unsigned number)
Address offset: 0x08
Read only = 0xXXXX XXXX where X is factory-programmed
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UID[95:80] | |||||||||||||||
| r | r | r | r | r | r | r | r | r | r | r | r | r | r | r | r |
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| UID[79:64] | |||||||||||||||
| r | r | r | r | r | r | r | r | r | r | r | r | r | r | r | r |
Bits 31:0 UID[95:64] : LOT_NUM[55:24]
Lot number (ASCII encoded)
53.2 Flash size data register
Base address: 0x0BFA 05E0
Address offset: 0x00
Read only = 0xXXXX where X is factory-programmed
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| FLASH_SIZE | |||||||||||||||
| r | r | r | r | r | r | r | r | r | r | r | r | r | r | r | r |
Bits 15:0 FLASH_SIZE[15:0] : Flash memory size
This bitfield indicates the size of the device flash memory expressed in Kbytes.
As an example, 0x040 corresponds to 64 Kbytes.
53.3 Package data register
Base address: 0x0BFA 0500
Address offset: 0x00
Read only = 0xXXXX where X is factory-programmed
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Res. | Res. | Res. | Res. | Res. | Res. | Res. | Res. | Res. | Res. | Res. | PKG[4:0] | ||||
| r | r | r | r | r | |||||||||||
Bits 15:5 Reserved, must be kept at reset value
Bits 4:0 PKG[4:0] : Package type
00000: LQFP64
00010: LQFP100
00011: UFBGA132
00100: LQFP144
00101: WLCSP81
01011: LQFP48 and UFQFPN48
10001: LQFP144 with SMPS Step Down converter
10010: UFBGA132 with SMPS Step Down converter
10011: LQFP100 with SMPS Step Down converter
10100: WLCSP81 with SMPS Step Down converter
10101: LQFP64 with SMPS Step Down converter
10110: LQFP48 and UFQFPN48 with SMPS Step Down converter
11000: LQFP144 with external SMPS support
11001: UFBGA132 with external SMPS support
11010: LQFP100 with external SMPS support
11011: WLCSP81 with external SMPS support
11100: LQFP64 and with external SMPS support
11101: LQFP48 with external SMPS support
Others: reserved