AM29LV116BT-80RFEB View Datasheet(PDF) - Advanced Micro Devices
Part Name
Description
Manufacturer
AM29LV116BT-80RFEB
Advanced Micro Devices
AM29LV116BT-80RFEB Datasheet PDF : 40 Pages
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PRELIMINARY
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 location.
The register is composed of latches that store the com-
mands, along with the address and data information
needed to execute the command. The contents of the
register serve as inputs to the internal state machine.
The state machine outputs dictate the function of the
device. Table 1 lists the device bus operations, the in-
puts and control levels they require, and the resulting
output. The following subsections describe each of
these operations in further detail.
Table 1. Am29LV116B Device Bus Operations
Operation
CE#
OE# WE# RESET#
Addresses
DQ0–DQ7
Read
Write
Standby
L
L
H
H
AIN
L
H
L
H
AIN
VCC ±
0.3 V
X
X
VCC ±
0.3 V
X
DOUT
DIN
High-Z
Output Disable
L
H
H
H
X
High-Z
Reset
X
X
X
L
X
High-Z
Sector Protect (See Note)
L
H
L
VID
Sector Addresses,
A6 = L, A1 = H, A0 = L
DIN, DOUT
Sector Unprotect (See Note)
L
H
L
VID
Sector Addresses
A6 = H, A1 = H, A0 = L
DIN, DOUT
Temporary Sector Unprotect
X
X
X
VID
AIN
DIN
Legend:
L = Logic Low = VIL, H = Logic High = VIH, VID = 12.0 ± 0.5 V, X = Don’t Care, AIN = Address In, DIN = Data In, DOUT = Data Out
Note: The sector protect and sector unprotect functions may also be implemented via programming equipment. See the “Sector
Protection/Unprotection” section.
Requirements for Reading Array Data
To read array data from the outputs, the system must
drive the CE# and OE# pins to VIL. CE# is the power
control and selects the device. OE# is the output con-
trol and gates array data to the output pins. WE#
should remain at VIH.
The internal state machine is set for reading array data
upon device power-up, or after a hardware reset. This
ensures that no spurious alteration of the memory con-
tent occurs during the power transition. No command is
necessary in this mode to obtain array data. Standard
microprocessor read cycles that assert valid addresses
on the device address inputs 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. ICC1 in
the DC Characteristics table represents the active cur-
rent specification for reading array data.
Writing Commands/Command Sequences
To write a command or command sequence (which in-
cludes programming data to the device and erasing
sectors of memory), the system must drive WE# and
CE# to VIL, and OE# to VIH.
The device features an Unlock Bypass mode to facil-
itate faster programming. Once the device enters the
Unlock Bypass mode, only two write cycles are re-
quired to program a byte, instead of four. The “Byte
Program Command Sequence” section has details on
programming data to the device using both standard
and Unlock Bypass command sequences.
An erase operation can erase one sector, multiple sec-
tors, or the entire device. Tables 2 and 3 indicate the
address space that each sector occupies. A “sector ad-
dress” consists of the address bits required to uniquely
select a sector. The “Command Definitions” section
has details on erasing a sector or the entire chip, or
suspending/resuming the erase operation.
After the system writes the autoselect command se-
quence, the device enters the autoselect mode. The
system can then read autoselect codes from the inter-
nal register (which is separate from the memory array)
on DQ7–DQ0. Standard read cycle timings apply in this
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Am29LV116B
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