MX29LV640D MCNIX [Macronix International], MX29LV640D Datasheet - Page 16

• Manufacturer Part Number: MX29LV640D
• Description: 64M-BIT [8M x 8/4M x 16] SINGLE VOLTAGE 3V
• Manufacturer: MCNIX [Macronix International]

MX29LV640D T/B
RESET# OPERATION
Driving RESET# pin low for a period more than Trp will reset the device back to read mode. If the device is in program
or erase operation, the reset operation will take at most a period of Tready for the device to return to read array mode.
Before the device returns to read array mode, the RY/BY# pin remains low (busy status).
When RESET# pin is held at GND±0.3V, the device consumes standby current(Isb).However, device draws larger
current if RESET# pin is held at Vil but not within GND±0.3V.
It is recommended that the system to tie its reset signal to RESET# pin of flash memory, so that the flash memory will
be reset during system reset and allows system to read boot code from flash memory.
SECTOR GROUP PROTECT OPERATION
When a sector group is protected, program or erase operation will be disabled on these sectors. MX29LV640D T/B
provides two methods for sector group protection.
Once the sector group is protected, the sector group remains protected until next chip unprotect, or is temporarily
unprotected by asserting RESET# pin at Vhv. Refer to temporary sector group unprotect operation for further details.
The first method is by applying Vhv on RESET# pin. Refer to Figure 13 for timing diagram and Figure 14 for the
algorithm for this method.
The other method is asserting Vhv on A9 and OE# pins, with A6 and CE# at Vil. The protection operation begins at the
falling edge of WE# and terminates at the rising edge. Contact Macronix for details.
CHIP UNPROTECT OPERATION
MX29LV640D T/B provides two methods for chip unprotect. The chip unprotect operation unprotects all sectors within
the device. It is recommended to protect all sectors before activating chip unprotect mode. All sectors groups are
unprotected when shipped from the factory.
The first method is by applying Vhv on RESET# pin. Refer to Figure 13 for timing diagram and Figure 14 for algorithm
of the operation.
The other method is asserting Vhv on A9 and OE# pins, with A6 at Vih and CE# at Vil. The unprotect operation begins
at the falling edge of WE# and terminates at the rising edge. Contact Macronix for details.
TEMPORARY SECTOR GROUP UNPROTECT OPERATION
System can apply RESET# pin at Vhv to place the device in temporary unprotect mode. In this mode, previously
protected sectors can be programmed or erased just as it is unprotected. The devices returns to normal operation once
Vhv is removed from RESET# pin and previously protected sectors are again protected.
P/N:PM1208
REV. 1.6, AUG. 16, 2008
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