Infineon XENSIV TLI4971 - Page 20

Application Note 20 of 31 Rev. 1.30
2022-03-01
Current Sensor TLI4971
Programming Guide and User Manual
threshold a '0' is stored in the EEPROM registers. By sweeping the external margin voltage the effective
threshold voltages of each EEPROM cell can be identified. The threshold voltages of cells programmed to '1'
can be found in this way. The smallest possible margin voltage is 0V, it is therefore not possible to determine
the threshold voltages below 0V for the cells programmed to '0'.
Table 14 EEPROM margin test
Command name
address
hex
command
hex
description
Enter Interface
---
DCBA
hex
Enter interface
Power down ISM
25
hex
8250
hex
8000
hex
Write command: get access to the register
Set data
Disable failure indication
01
hex
8010
hex
0000
hex
Write command
Set data
Read all register
Read data before modifying values
Read all EEPROM for
reference
40
hex
n
51
hex
0400
hex
00n0
0510
hex
Read command at EEPROM line 0
Read command for address “n”
Address last line in EEPROM
NOP
---
FFFF
hex
Read values from previous address
Loop reference voltage on OCD2:
Sweep voltage from start voltage till end voltage in
defined step-size
Send “margin” command
3E
hex
83E0
hex
0045
hex
Write to EEPROM command line
Set margin test “zeros” (0044
hex
= “ones”)
Apply actual reference voltage for comparison and
wait 2ms
Send “margin stop”
3E
hex
83E0
hex
0080
hex
Write to EEPROM command line
Stop margin test
Wait 100 µs
Read all EEPROM for
comparison
40
hex
n
51
hex
0400
hex
00n0
0510
hex
Read command at EEPROM line 0
Read command for address “n”
Address last line in EEPROM
LoopEnd
Find threshold-voltage when EEPROM cell flipped
Compare all EEPROM-content at each voltage to
reference