MX26LV800T Macronix, MX26LV800T Datasheet - Page 17

• Manufacturer Part Number: MX26LV800T
• Description: 8M-Bit CMOS Single Voltage Flash Memory
• Manufacturer: Macronix

Q3
Sector Erase Timer
After the completion of the initial sector erase command
sequence, the sector erase time-out will begin. Q3 will
remain low until the time-out is complete. Data# Polling
and Toggle Bit are valid after the initial sector erase com-
mand sequence.
If Data# Polling or the Toggle Bit indicates the device
has been written with a valid erase command, Q3 may
be used to determine if the sector erase timer window is
still open. If Q3 is high ("1") the internally controlled
erase cycle has begun; attempts to write subsequent
commands to the device will be ignored until the erase
operation is completed as indicated by Data# Polling or
Toggle Bit. If Q3 is low ("0"), the device will accept
additional sector erase commands. To insure the com-
mand has been accepted, the system software should
check the status of Q3 prior to and following each sub-
sequent sector erase command. If Q3 were high on the
second status check, the command may not have been
accepted.
DATA PROTECTION
The MX26LV800T/B is designed to offer protection
against accidental erasure or programming caused by
spurious system level signals that may exist during power
transition. During power up the device automatically re-
sets the state machine in the Read mode. In addition,
with its control register architecture, alteration of the
memory contents only occurs after successful comple-
tion of specific command sequences. The device also
incorporates several features to prevent inadvertent write
cycles resulting from VCC power-up and power-down tran-
sition or system noise.
WRITE PULSE "GLITCH" PROTECTION
Noise pulses of less than 5ns(typical) on CE# or WE#
will not initiate a write cycle.
LOGICAL INHIBIT
Writing is inhibited by holding any one of OE# = VIL,
CE# = VIH or WE# = VIH. To initiate a write cycle CE#
and WE# must be a logical zero while OE# is a logical
one.
P/N:PM1007
17
POWER SUPPLY DECOUPLING
In order to reduce power switching effect, each device
should have a 0.1uF ceramic capacitor connected be-
tween its VCC and GND.
POWER-UP SEQUENCE
The MX26LV800T/B powers up in the Read only mode.
In addition, the memory contents may only be altered
after successful completion of the predefined command
sequences.
MX26LV800T/B
REV. 1.2, JUL. 08, 2004