MX29LV040C
CHIP UNPROTECT
The MX29LV040C also features the chip unprotect mode,
so that all sectors are unprotected after chip unprotect
is completed to incorporate any changes in the code. It
is recommended to protect all sectors before activating
chip unprotect mode.
To activate this mode, the programming equipment must
force VID on control pin OE# and address pin A9. The
CE# pins must be set at VIL. Pins A6 must be set to
VIH. Refer to chip unprotect algorithm and waveform for
the chip unprotect algorithm. The unprotected mecha-
nism begins on the falling edge of the WE# pulse and is
terminated on the rising edge.
It is also possible to determine if the chip is unprotected
in the system by writing the Read Silicon ID command.
Performing a read operation with A1=VIH, it will produce
00H at data outputs(Q0-Q7) for an unprotected sector.
It is noted that all sectors are unprotected after the chip
unprotect algorithm is completed.
P/N:PM1149
REV. 1.3, APR. 24, 2006
16