EM39LV040
4M (512Kx8) Bits Flash Memory
SPECIFICATION
Hardware Data Protection
Noise/Glitch Protection: A WE# or CE# pulse of less than 5 ns will not initiate a
write cycle.
VDD Power Up/Down Detection: The Write operation is inhibited when VDD is less than
1.5V.
Write Inhibit Mode: Forcing OE# Low, CE# High, or WE# High will inhibit the
Write operation. This prevents inadvertent write during
power-up or power-down.
Software Data Protection (SDP)
The EM39LV040 provides the JEDEC approved Software Data Protection (SDP) scheme for
Program and Erase operations. Any Program operation requires the inclusion of the
three-byte sequence. The three-byte load sequence is used to initiate the Program operation,
providing optimal protection from inadvertent Write operations, especially during the system
power-up or power-down transition. Any Erase operation requires the inclusion of six-byte
sequence. See Table 3 below for the specific software command codes. During SDP
command sequence, invalid commands will abort the device to Read mode within TRC
.
Software Command Sequence
1st Bus
2nd Bus
3rd Bus
4th Bus
5th Bus
6th Bus
Command
Sequence
Write Cycle Write Cycle Write Cycle Write Cycle Write Cycle Write Cycle
Addr1 Data
5555H AAH 2AAAH 55H 5555H A0H
5555H AAH 2AAAH 55H 5555H 80H 5555H AAH 2AAAH 55H
Addr1
Data Addr1 Data Addr1 Data
Addr1
Data Addr1 Data
Byte Program
Sector Erase
Chip Erase
BA2
Data
3
SAX
30H
5555H AAH 2AAAH 55H 5555H 80H 5555H AAH 2AAAH 55H 5555H 10H
5555H AAH 2AAAH 55H 5555H 90H
Software ID
Entry4
Manufacture ID
Manufacture ID
Manufacture ID
Device ID
5555H AAH 2AAAH 55H 5555H 90H 0000H 7FH
5555H AAH 2AAAH 55H 5555H 90H 0003H 7FH
5555H AAH 2AAAH 55H 5555H 90H 0040H 1FH
5555H AAH 2AAAH 55H 5555H 90H 0001H 29FH
Software ID Exit5 XXH
F0H
Software ID Exit5 5555H AAH 2AAAH 55H 5555H F0H
Notes:
1. Address format A18-A0 (Hex) & Address A16 can be VIL or VIH, (but no other value) for the Command sequence.
2. BA = Program byte address.
3. SAX for Sector-Erase; uses A19-A12 address lines.
4. The device does not remain in Software Product ID mode if powered down (see Figure 9 for more information).
5. Both Software ID Exit operations are equivalent.
Table 3: Software Command Sequence
This specification is subject to change without further notice. (07.22.2004 V1.0)
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ELAN [ ELAN MICROELECTRONICS CORP ]
