S29PL032J SPANSION [SPANSION], S29PL032J Datasheet - Page 61

• Manufacturer Part Number: S29PL032J
• Description: CMOS 3.0 Volt-only, Simultaneous Read/Write Flash Memory with Enhanced VersatileIO Control
• Manufacturer: SPANSION [SPANSION]

April 7, 2005 31107A62
Hardware Data Protection
The command sequence requirement of unlock cycles for programming or erasing
provides data protection against inadvertent writes. In addition, the following
hardware data protection measures prevent accidental erasure or programming,
which might otherwise be caused by spurious system level signals during V
power-up and power-down transitions, or from system noise.
Low V
When V
tects data during V
internal program/erase circuits are disabled, and the device resets to the read
mode. Subsequent writes are ignored until V
must provide the proper signals to the control pins to prevent unintentional writes
when V
Write Pulse “Glitch” Protection
Noise pulses of less than 3 ns (typical) on OE#, CE#, (CE1#, CE2# in PL129J) or
WE# do not initiate a write cycle.
Logical Inhibit
Write cycles are inhibited by holding any one of OE# = V
in PL129J)= V
PL129J) and WE# must be a logical zero while OE# is a logical one.
Power-Up Write Inhibit
If WE# = CE# (CE1#, CE2# in PL129J) = V
the device does not accept commands on the rising edge of WE#. The internal
state machine is automatically reset to the read mode on power-up.
CC
CC
CC
Write Inhibit
is greater than V
is less than V
IH
or WE# = V
P R E L I M I N A R Y
CC
Figure 3. SecSi Sector Protect Verify
S29PL127J/S29PL129J/S29PL064J/S29PL032J
power-up and power-down. The command register and all
Write 40h to SecSi
LKO
Read from SecSi
Sector address
Sector address
A1 = 1, A0 = 0
A1 = 1, A0 = 0
Write 60h to
any address
with A6 = 0,
with A6 = 0,
, the device does not accept any write cycles. This pro-
RESET# =
V
LKO
Wait 1 µs
START
IH
IH
.
or V
. To initiate a write cycle, CE# (CE1# / CE2# in
ID
Remove V
SecSi Sector is
SecSi Sector is
If data = 00h,
If data = 01h,
from RESET#
Protect Verify
SecSi Sector
unprotected.
CC
IL
Write reset
protected.
command
complete
and OE# = V
is greater than V
IH
or V
ID
IL
, CE# (CE1# = CE2#
IH
during power up,
LKO
. The system
CC
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