X28LC512 Datasheet, PDF (8/19 Pages) Xicor Inc. – 3.3 Volt, Byte Alterable E2PROM

X28LC512/X28LC513
Resetting Software Data Protection
Figure 5a. Reset Software Data Protection Timing Sequence
VCC
DATA AA
ADDR 5555
CE
55
2AAA
80
5555
AA
5555
55
2AAA
20
5555
WE
≥tWC
STANDARD
OPERATING
MODE
NOTE: All other timings and control pins are per page write timing requirements.
3005 ILL F18
Figure 5b. Software Sequence to Deactivate
Software Data Protection
WRITE DATA AA
TO ADDRESS
5555
WRITE DATA 55
TO ADDRESS
2AAA
In the event the user wants to deactivate the software
data protection feature for testing or reprogramming in
an E²PROM programmer, the following six step algo-
rithm will reset the internal protection circuit. After t_WC,
the X28LC512/513 will be in standard operating mode.
Note: Once initiated, the sequence of write operations
should not be interrupted.
WRITE DATA 80
TO ADDRESS
5555
WRITE DATA AA
TO ADDRESS
5555
WRITE DATA 55
TO ADDRESS
2AAA
WRITE DATA 20
TO ADDRESS
5555
3005 FHD F19
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