AM29F010B ETC, AM29F010B Datasheet - Page 12

• Manufacturer Part Number: AM29F010B
• Description: 1 Megabit (128 K x 8-bit) CMOS 5.0 Volt-only/ Uniform Sector Flash Memory
• Manufacturer: ETC

L = Logic Low = V
Sector Protection/Unprotection
The hardware sector protection feature disables both
program and erase operations in any sector. The hard-
ware sector unprotection feature re-enables both
program and erase operations in previously protected
sectors.
Sector protection/unprotection must be implemented
using programming equipment. The procedure re-
quires a high voltage (V
control pins. Details on this method are provided in a
supplement, publication number 22337. Contact an
AMD representative to obtain a copy of the appropriate
document.
The device is shipped with all sectors unprotected.
AMD offers the option of programming and protecting
sectors at its factory prior to shipping the device
through AMD’s ExpressFlash™ Service. Contact an
AMD representative for details.
It is possible to determine whether a sector is protected
or unprotected. See “Autoselect Mode” for details.
Hardware Data Protection
The command sequence requirement of unlock cycles
for programming or erasing provides data protection
against inadvertent writes (refer to the Command Defi-
nitions table). In addition, the following hardware data
protection measures prevent accidental erasure or pro-
November 18, 2002
Manufacturer ID: AMD
Device ID: Am29F010B
Sector Protection Verification
Description
IL
, H = Logic High = V
Table 3. Am29F010B Autoselect Codes (High Voltage Method)
ID
) on address pin A9 and the
CE#
L
L
L
IH
, SA = Sector Address, X = Don’t care.
OE#
L
L
L
WE#
H
H
H
Am29F010B
A16
A14
SA
to
X
X
A13
A10
to
X
X
X
gramming, which might otherwise be caused by
spurious system level signals during V
and power-down transitions, or from system noise.
Low V
When V
cept any write cycles. This protects data during V
power-up and power-down. The command register and
all internal program/erase circuits are disabled, and the
device resets. Subsequent writes are ignored until V
is greater than V
proper signals to the control pins to prevent uninten-
tional writes when V
Write Pulse “Glitch” Protection
Noise pulses of less than 5 ns (typical) on OE#, CE# or
WE# do not initiate a write cycle.
Logical Inhibit
Write cycles are inhibited by holding any one of OE# =
V
CE# and WE# must be a logical zero while OE# is a
logical one.
Power-Up Write Inhibit
If WE# = CE# = V
device does not accept commands on the rising edge
of WE#. The internal state machine is automatically
reset to reading array data on power-up.
IL
, CE# = V
V
V
V
A9
ID
ID
ID
CC
CC
Write Inhibit
A8
A7
is less than V
to
X
X
X
IH
or WE# = V
IL
A6
LKO
L
L
L
and OE# = V
CC
. The system must provide the
is greater than V
A5
A2
to
X
X
X
LKO
IH
, the device does not ac-
. To initiate a write cycle,
A1
H
L
L
IH
during power up, the
A0
H
L
L
LKO
(unprotected)
CC
(protected)
.
power-up
DQ7
DQ0
01h
20h
01h
00h
to
11
CC
CC