SRT512-W4/1GE STMicroelectronics, SRT512-W4/1GE Datasheet - Page 15

• Manufacturer Part Number: SRT512-W4/1GE
• Manufacturer: STMicroelectronics

Specifications of SRT512-W4/1GE

• Operating Temperature (max): 85C
• Mounting: Surface Mount
• Operating Temperature Classification: Commercial
• Lead Free Status / RoHS Status: Supplier Unconfirmed

SRT512
4.1
4.2
EEPROM area
Blocks 0 to 4 define a User area. They behave as standard EEPROM blocks, like blocks 7 to
15 as described in
OTP_Lock_Reg bits of the system area. Once a block has been protected, it can no longer
be unprotected.
Figure 13. Lockable EEPROM area (addresses 0 to 4)
32-bit binary counters
The two 32-bit binary counters located at block addresses 5 and 6, respectively, are used to
count down from 2
the update of a counter if the new value is lower than the previous one. This feature allows
the application to count down by steps of 1 or more. The initial value is FFFF FFFEh in
counter 5 and, FFFF FFFFh in counter 6. When the value displayed is 0000 0000h, the
counter is empty and cannot be reloaded. The counter is updated by issuing the Write_block
command to block address 5 or 6, depending on which counter is to be updated. The
Write_block command writes the new 32-bit value to the counter block address.
shows examples of how the counters operate.
The counter programming cycles are protected by automated antitearing logic. This function
allows the counter value to be protected in case of power down within the programming
cycle. In case of power down, the counter value is not updated and the previous value
continues to be stored.
Blocks 5 and 6 can be write-protected using the OTP_Lock_Reg bits (block 255). Once a
block has been protected, its contents cannot be modified. A protected counter block
behaves like a ROM block.
Figure 14. Binary counter (addresses 5 to 6)
address
Block
0
1
2
3
4
Block
address
5
6
MSb
b31
b31
MSb
32
Figure
(4096 million) to 0. The SRT512 uses dedicated logic that only allows
13. Each block can be individually write-protected using the
Doc ID 13277 Rev 4
b16 b15 b14
32-bit binary counter
32-bit binary counter
32-bit block
User area
User area
User area
User area
User area
b16 b15 b14
32-bit block
b8 b7
b8 b7
LSb
b0
LSb
b0
Memory mapping
EEPROM
Lockable
Description
Description
Count down
counter
Figure 15
ai12384b
ai12382b
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