D A T A S H E E T
DEVICE BUS OPERATIONS
This section describes the requirements and use of
the device bus operations, which are initiated through
the internal command register. The command register
itself does not occupy any addressable memory loca-
tion. The register is composed of latches that store the
commands, along with the address and data informa-
tion needed to execute the command. The contents of
the register serve as inputs to the internal state ma-
chine. The state machine outputs dictate the function
of the device. Table 1 lists the device bus operations,
the inputs and control levels they require, and the re-
sulting output. The following subsections describe
each of these operations in further detail.
Table 1. Am29LV160D Device Bus Operations
DQ8–DQ15
BYTE#
= V
Addresses
(Note 1)
DQ0– BYTE#
Operation
CE# OE# WE# RESET#
DQ7
= V
IH
IL
Read
Write
L
L
L
H
L
H
H
A
D
D
DQ8–DQ14 = High-Z,
DQ15 = A-1
IN
OUT
OUT
H
A
D
D
IN
IN
IN
V
0.3 V
±
V
0.3 V
±
CC
CC
Standby
X
X
X
High-Z High-Z
High-Z
Output Disable
Reset
L
H
X
H
X
H
L
X
X
High-Z High-Z
High-Z High-Z
High-Z
High-Z
X
Sector Address,
A6 = L, A1 = H,
A0 = L
Sector Protect (Note 2)
L
H
L
V
D
X
X
X
ID
IN
Sector Address,
A6 = H, A1 = H,
A0 = L
Sector Unprotect (Note 2)
L
H
X
L
V
V
D
D
X
ID
ID
IN
IN
Temporary Sector
Unprotect
X
X
A
D
High-Z
IN
IN
Legend:
L = Logic Low = V , H = Logic High = V , V = 12.0 ± 0.5 V, X = Don’t Care, A = Address In, D = Data In, D = Data Out
IL
IH
ID
IN
IN
OUT
Notes:
1. Addresses are A19:A0 in word mode (BYTE# = V ), A19:A-1 in byte mode (BYTE# = V ).
IH
IL
2. The sector protect and sector unprotect functions may also be implemented via programming equipment. See the “Sector
Protection/Unprotection” section.
The internal state machine is set for reading array
Word/Byte Configuration
data upon device power-up, or after a hardware re-
The BYTE# pin controls whether the device data I/O
set. This ensures that no spurious alteration of the
pins DQ15–DQ0 operate in the byte or word configura-
memory content occurs during the power transition.
tion. If the BYTE# pin is set at logic ‘1’, the device is in
No command is necessary in this mode to obtain
word configuration, DQ15–DQ0 are active and con-
array data. Standard microprocessor read cycles that
trolled by CE# and OE#.
assert valid addresses on the device address inputs
If the BYTE# pin is set at logic ‘0’, the device is in byte
configuration, and only data I/O pins DQ0–DQ7 are
active and controlled by CE# and OE#. The data I/O
pins DQ8–DQ14 are tri-stated, and the DQ15 pin is
used as an input for the LSB (A-1) address function.
produce valid data on the device data outputs. The
device remains enabled for read access until the
command register contents are altered.
See “Reading Array Data” for more information. Refer
to the AC Read Operations table for timing specifica-
tions and to Figure 13 for the timing diagram. I
the DC Characteristics table represents the active cur-
rent specification for reading array data.
in
CC1
Requirements for Reading Array Data
To read array data from the outputs, the system must
drive the CE# and OE# pins to V . CE# is the power
IL
control and selects the device. OE# is the output control
and gates array data to the output pins. WE# should re-
Writing Commands/Command Sequences
To write a command or command sequence (which in-
cludes programming data to the device and erasing
main at V . The BYTE# pin determines whether the
IH
device outputs array data in words or bytes.
22358B7 May 5, 2006
Am29LV160D
9
AMD [ AMD ]
