SRIX4K-SBN181GE STMICROELECTRONICS [STMicroelectronics], SRIX4K-SBN181GE Datasheet - Page 15

• Manufacturer Part Number: SRIX4K-SBN181GE
• Description: 13.56 MHz short-range contactless memory chip with 4096-bit EEPROM, anticollision and anti-clone functions
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

SRIX4K
4.1
Resettable OTP area
In this area contains five individual 32-bit Boolean words (see
area). A Write_block command will not erase the previous contents of the block as the write
cycle is not preceded by an auto-erase cycle. This feature can be used to reset selected bits
from 1 to 0. All bits previously at 0 remain unchanged. When the 32 bits of a block are all at
0, the block is empty, and cannot be updated any more. See
examples of the result of the Write_block command in the resettable OTP area.
Figure 13. Resettable OTP area (addresses 0 to 4)
Figure 14. Write_block update in Standard mode (binary format)
The five 32-bit blocks making up the resettable OTP area can be erased in one go by adding
an auto-erase cycle to the Write_block command. An auto-erase cycle is added each time
the SRIX4K detects a Reload command. The Reload command is implemented through a
specific update of the 32-bit binary counter located at block address 6 (see
bit binary counters
Previous data stored in block
Data to be written
New data stored in block
Block
address
0
1
2
3
4
MSb
b31
for details).
b31
b24 b23
1
1
1
...
...
...
1
1
1
32-bit Boolean area
32-bit Boolean area
32-bit Boolean area
32-bit Boolean area
32-bit Boolean area
1
0
0
32-bit block
b16 b15
0
0
0
1
1
1
0
0
0
1
1
1
b8 b7
Figure 14
1
1
1
Figure 13
1
0
0
LSb
b0
1
0
0
and
for a map of the
Memory mapping
1
1
1
Section 4.2: 32-
Figure 15
Resettable
OTP bit
Description
0
1
0
1
1
1
ai07657b
ai07658
for
15/47
1
1
1
b0