read-while-program and read-while-erase current
specifications.
The AC Characteristics section contains timing specifi-
cation tables and timing diagrams for erase or pro-
gram operations.
Simultaneous read/write operations are valid for both
the main Flash memory array and the SecSi OTP sec-
tor. Simultaneous operation is disabled during the CFI
and Password Program/Verify operations. PPB Pro-
gram/Erase operations and the Password Unlock op-
eration permit reading data from the large (75%) bank
while reading the operation status of these commands
from the small (25%) bank.
Accelerated Program and Erase Operations
The device offers accelerated program/erase opera-
tions through the ACC pin. When the system asserts
VHH (12V) on the ACC pin, the device automatically
enters the Unlock Bypass mode. The system may
then write the two-cycle Unlock Bypass program com-
mand sequence to do accelerated programming. The
device uses the higher voltage on the ACC pin to ac-
celerate the operation. A sector that is being protected
with the WP# pin will still be protect during accelerated
program or Erase. Note that the ACC pin must not be
at VHH during any operation other than accelerated
programming, or device damage may result.
Table 3. Top Boot Bank Select
Bank
Bank 1
Bank 2
A18:A17
00
01, 1X
Table 4. Bottom Boot Bank Select
Bank
A18
0X, 10
11
Autoselect Functions
Bank 1
Bank 2
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 DQ7–DQ0. Standard read cycle timings apply in
this mode. Refer to the Autoselect Mode and Autose-
lect Command Sequence sections for more informa-
tion.
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.
For program operations, in the x32-mode the device
accepts program data in 32-bit words and in the x16
mode the device accepts program data in 16-bit
words.
Automatic Sleep Mode (ASM)
The automatic sleep mode minimizes Flash device en-
ergy consumption. While in asynchronous mode, the
device automatically enables this mode when ad-
dresses remain stable for tACC + 60 ns. The automatic
sleep mode is independent of the CE#, WE# and OE#
control signals. Standard address access timings pro-
vide new data when addresses are changed. While in
sleep mode, output data is latched and always avail-
able to the system. While in synchronous mode, the
device automatically enables this mode when either
the first active CLK level is greater than tACC or the
CLK runs slower than 5 MHz. Note that a new burst
operation is required to provide new data.
The device features an Unlock Bypass mode to facili-
tate faster programming. Once the device enters the
Unlock Bypass mode, only two write cycles are re-
quired to program a word or byte, instead of four. The
Sector Erase and Program Suspend Command sec-
tion has details on programming data to the device
using both standard and Unlock Bypass command se-
quences.
An erase operation can erase one sector, multiple sec-
tors, or the entire device. Tables 12 and 13 indicate
the address space that each sector occupies. A “sec-
tor address” 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.
ICC8 in the “DC Characteristics” section of page 53 rep-
resents the automatic sleep mode current specifica-
tion.
Standby Mode
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 timing applies in
this mode. Refer to the “Autoselect Mode” section for
more information.
When the system is not responding or writing to the
device, 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.
The device enters the CMOS standby mode when the
CE# and RESET# inputs are both held at Vcc ± ±0.2 V.
The device requires standard access time (tCE) for
read access, before it is ready to read data.
ICC2 in the DC Characteristics table represents the ac-
tive current specification for erase or program modes.
14
Am29BDD160G
June 7, 2006