AM29PDL640AGA85NS SPANSION [SPANSION], AM29PDL640AGA85NS Datasheet - Page 13

• Manufacturer Part Number: AM29PDL640AGA85NS
• Description: 64 Megabit (4 M x 16-Bit) CMOS 3.0 Volt-only, Simultaneous Operation Flash Memory and 16 Mbit (1 M x 16-Bit) Pseudo Static RAM
• Manufacturer: SPANSION [SPANSION]

Requirements for Reading Array Data
To read array data from the outputs, the system must
drive the CE# and OE# pins to V
control and selects the device. OE# is the output con-
trol and gates array data to the output pins. WE#
should remain at V
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
content occurs during the power transition. No com-
mand 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. Each bank remains
enabled for read access until the command register
contents are altered.
Refer to the AC Read-Only Operations table for timing
specifications and to Figure 14 for the timing diagram.
I
tive current specification for reading array data.
Random Read (Non-Page Read)
Address access time (t
stable addresses to valid output data. The chip enable
access time (t
dresses and stable CE# to valid data at the output in-
puts. The output enable access time is the delay from
the falling edge of the OE# to valid data at the output
inputs (assuming the addresses have been stable for
at least t
Page Mode Read
The device is capable of fast page mode read and is
compatible with the page mode Mask ROM read oper-
ation. This mode provides faster read access speed
for random locations within a page. The page size of
the device is 8 words, with the appropriate page being
selected by the higher address bits A21–A3 and the
LSB bits A2–A0 determining the specific word within
that page. This is an asynchronous operation with the
microprocessor supplying the specific word location.
The random or initial page access is equal to t
t
the locations specified by the microprocessor falls
within that page) is equivalent to t
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.
November 20, 2003
CC1
CE
and subsequent page read accesses (as long as
in the DC Characteristics table represents the ac-
ACC
–t
OE
CE
time).
) is the delay from the stable ad-
IH
ACC
.
or t
ACC
CE
) is equal to the delay from
. Here again, CE# selects
IL
PACC
. CE# is the power
. When CE# is
P R E L I M I N A R Y
ACC
Am49PDL640AG
or
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-
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
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 2. Page Select
Table 3. Bank Select
IH
.
A2
0
0
0
0
1
1
1
1
001, 010, 011
100, 101, 110
A21–A19
A1
0
0
1
1
0
0
1
1
000
111
A0
0
1
0
1
0
1
0
1
11