AM29PDL640G AMD [Advanced Micro Devices], AM29PDL640G Datasheet - Page 14

• Manufacturer Part Number: AM29PDL640G
• Description: 64 Megabit (4 M x 16-Bit) CMOS 3.0 Volt-only, Simultaneous Read/Write Flash Memory with Enhanced VersatileIOTM Control
• Manufacturer: AMD [Advanced Micro Devices]

deasserted and reasserted for a subsequent access,
the access time is t
the device and OE# is the output control and should
be used to gate data to the output inputs if the device
is selected. Fast page mode accesses are obtained by
keeping A21–A3 constant and changing A2 to A0 to
select the specific word within that page.
Simultaneous Operation
The device is capable of reading data from one bank
of memory while a program or erase operation is in
progress in another bank of memory (simultaneous
operation), in addition to the conventional features
(read, program, erase-suspend read, and erase-sus-
pend program). The bank selected can be selected by
bank addresses (A21–A19) with zero latency.
The simultaneous operation can execute multi-func-
tion mode in the same bank.
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 V
The device features an Unlock Bypass mode to facili-
tate faster programming. Once a bank enters the Un-
lock Bypass mode, only two write cycles are required
to program a word, instead of four. The “Word Pro-
12
Word 0
Word 1
Word 2
Word 3
Word 4
Word 5
Word 6
Word 7
Word
IL
Bank A
Bank B
Bank C
Bank D
, and OE# to V
Bank
Table 3. Bank Select
Table 2. Page Select
ACC
or t
IH
CE
.
A2
0
0
0
0
1
1
1
1
. Here again, CE# selects
001, 010, 011
100, 101, 110
A21–A19
A1
0
0
1
1
0
0
1
1
000
111
D A T A S H E E T
A0
0
1
0
1
0
1
0
1
Am29PDL640G
gram 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. Table 4 indicates the address
space that each sector occupies. A “bank address” is
the address bits required to uniquely select a bank.
Similarly, a “sector address” refers to 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 op-
eration.
I
tive current specification for the write mode. The
Characteristics
tables and timing diagrams for write operations.
Accelerated Program Operation
The device offers accelerated program operations
through the ACC function. This function is primarily in-
tended to allow faster manufacturing throughput at the
factory.
If the system asserts V
matically enters the aforementioned Unlock Bypass
mode, temporarily unprotects any protected sectors,
and uses the higher voltage on the pin to reduce the
time required for program operations. The system
would use a two-cycle program command sequence
as required by the Unlock Bypass mode. Removing
V
mal operation. Note that V
WP#/ACC for operations other than accelerated pro-
gramming, or device damage may result. In addition,
the WP#/ACC pin should be raised to V
use. That is, the WP#/ACC pin should not be left float-
ing or unconnected; inconsistent behavior of the de-
vice may result.
Autoselect Functions
If 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 DQ15–DQ0. Standard read cycle timings apply in
this mode. Refer to the
lect Command Sequence
tion.
Standby Mode
When the system is not reading or writing to the de-
vice, it can place the device in the standby mode. In
this mode, current consumption is greatly reduced,
and the outputs are placed in the high impedance
state, independent of the OE# input.
CC2
HH
in the DC Characteristics table represents the ac-
from the WP#/ACC pin returns the device to nor-
section contains timing specification
HH
Autoselect Mode
on this pin, the device auto-
HH
sections for more informa-
must not be asserted on
December 13, 2005
CC
and
when not in
Autose-
AC