Atmel DataFlash AT45DB321 Operation
Features
• Single 2.7V - 3.6V Supply
• Serial-interface Architecture
• Page Program Operation
– Single Cycle Reprogram (Erase and Program)
– 8192 Pages (528 Bytes/Page) Main Memory
• Optional Page and Block Erase Operations
• Two 528-byte SRAM Data Buffers – Allows Receiving of Data while Reprogramming of
Nonvolatile Memory
• Internal Program and Control Timer
• Fast Page Program Time – 7 ms Typical
• 120 µs Typical Page to Buffer Transfer Time
• Low-power Dissipation
– 4 mA Active Read Current Typical
– 3 µA CMOS Standby Current Typical
• 13 MHz Max Clock Frequency
• Hardware Data Protection Feature
• Serial Peripheral Interface (SPI) Compatible – Modes 0 and 3
• CMOS and TTL Compatible Inputs and Outputs
• Commercial and Industrial Temperature Ranges
32-megabit
2.7-volt Only
Serial
DataFlash
®
Description
The AT45DB321 is a 2.7-volt only, serial-interface Flash memory suitable for in-system reprogramming. Its 34,603,008 bits of memory are organized as 8192 pages of
528 bytes each. In addition to the main memory, the AT45DB321 also contains two
SRAM data buffers of 528 bytes each. The buffers allow receiving of data while a
page in the main memory is being reprogrammed. Unlike conventional Flash memo-
(continued)
Pin Configurations
Pin Name Function
CS
SCK Serial Clock
SI Serial Input
SO Serial Output
WP
RESET
RDY/BUSY
Chip Select
Hardware Page
Write Protect Pin
Chip Reset
Ready/Busy
CBGA Top View Through Package
2345
1
A
B
C
D
E
F
G
H
J
NC
NC
NC
NC
NC
NC
NC
SCK
NC
CS
NC
SO
NC
NC
NC
NC
NC
NC
NC
NC
GND
RDY/BSY
SI
NC
NC
NC
NC
NC
NC
VCC
WP
RESET
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
TSOP Top View
Type 1
RESET
WP
VCC
GND
SCK
1
2
3
4
NC
5
NC
6
NC
7
8
9
NC
10
NC
11
NC
12
NC
13
CS
14
15
SI
16
SO
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
RDY/BUSY
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
AT45DB321
Recommend using
AT45DB321B for new
designs.
AT45DB321
Preliminary 16Megabit 2.7-volt
Only Serial
DataFlash
Rev. 1121E–01/01
1
ries that are accessed randomly with multiple address lines
and a parallel interface, the DataFlash uses a serial interface to sequentially access its data. The simple serial interface facilitates hardware layout, increases system
reliability, minimizes switching noise, and reduces package
size and active pin count. The device is optimized for use in
many commercial and industrial applications where high
density, low pin count, low voltage, and low power are
essential. Typical applications for the DataFlash are digital
voice storage, image storage, and data storage. The
device operates at clock frequencies up to 13 MHz with a
typical active read current consumption of 4 mA.
Block Diagram
To allow for simple in-system reprogrammability, the
AT45DB321 does not require high input voltages for programming. The device operates from a single power supply, 2.7V to 3.6V, for both the program and read
operations. The AT45DB321 is enabled through the chip
select pin (CS
consisting of the Serial Input (SI), Serial Output (SO), and
the Serial Clock (SCK).
All programming cycles are self-timed, and no separate
erase cycle is required before programming.
) and accessed via a three-wire interface
WP
PAGE (528 BYTES)
SCK
CS
RESET
VCC
GND
RDY/BUSY
Memory Array
To provide optimal flexibility, the memory array of the
AT45DB321 is divided into three levels of granularity comprising of sectors, blocks, and pages. The Memory Architecture Diagram illustrates the breakdown of each level and
FLASH MEMORY ARRAY
BUFFER 2 (528 BYTES)BUFFER 1 (528 BYTES)
I/O INTERFACE
SOSI
details the number of pages per sector and block. All program operations to the DataFlash occur on a page by page
basis; however, the optional erase operations can be performed at the block or page level.
2
AT45DB321
Memory Architecture Diagram
SECTOR ARCHITECTURE BLOCK ARCHITECTURE PAGE ARCHITECTURE
SECTOR 0 = 4224 bytes (4K + 128)
SECTOR 1 = 266,112 bytes (252K + 8064)
SECTOR 0
BLOCK 0
BLOCK 1
BLOCK 2
8 Pages
AT45DB321
PAGE 0
PAGE 1
SECTOR 2 = 270,336 bytes (256K + 8192)
SECTOR 15 = 270,336 bytes (256K + 8192)
SECTOR 16 = 270,336 bytes (256K + 8192)
SECTOR 1
SECTOR 2
Block = 4224 bytes
Device Operation
The device operation is controlled by instructions from the
host processor. The list of instructions and their associated
opcodes are contained in Table 1 and Table 2. A valid
instruction starts with the falling edge of CS
appropriate 8-bit opcode and the desired buffer or main
memory address location. While the CS
the SCK pin controls the loading of the opcode and the
desired buffer or main memory address location through
the SI (serial input) pin. All instructions, addresses, and
data are transferred with the most significant bit (MSB) first.
Read
By specifying the appropriate opcode, data can be read
from the main memory or from either one of the two data
buffers.
MAIN MEMORY PAGE READ: A main memory read allows
the user to read data directly from any one of the 8192
pages in the main memory, bypassing both of the data buffers and leaving the contents of the buffers unchanged. To
start a page read, the 8-bit opcode, 52H, is followed by 24
address bits and 32 don’t care bits. In the AT45DB321, the
first address bit is reserved for larger density devices (see
Notes on page 10), the next 13 address bits (PA12-PA0)
specify the page address, and the next 10 address bits
(BA9-BA0) specify the starting byte address within the
followed by the
pin is low, toggling
BLOCK 0
BLOCK 62
BLOCK 63
BLOCK 64
BLOCK 65
BLOCK 1
BLOCK 126
BLOCK 127
BLOCK 128
BLOCK 129
BLOCK 1022
BLOCK 1023
(4K + 128)
PAGE 6
PAGE 7
PAGE 8
PAGE 9
PAGE 14
PAGE 15
PAGE 16
PAGE 17
PAGE 18
PAGE 8189
PAGE 8190
PAGE 8191
Page = 528 bytes
(512 + 16)
page. The 32 don’t care bits which follow the 24 address
bits are sent to initialize the read operation. Following the
32 don’t care bits, additional pulses on SCK result in serial
data being output on the SO (serial output) pin. The CS
must remain low during the loading of the opcode, the
address bits, and the reading of data. When the end of a
page in main memory is reached during a main memory
page read, the device will continue reading at the beginning
of the same page. A low to high transition on the CS
terminate the read operation and tri-state the SO pin.
BUFFER READ: Data can be read from either one of the
two buffers, using different opcodes to specify which buffer
to read from. An opcode of 54H is used to read data from
buffer 1, and an opcode of 56H is used to read data from
buffer 2. To perform a buffer read, the eight bits of the
opcode must be followed by 14 don’t care bits, 10 address
bits, and eight don't care bits. Since the buffer size is 528bytes, 10 address bits (BFA9-BFA0) are required to specify
the first byte of data to be read from the buffer. The CS
must remain low during the loading of the opcode, the
address bits, the don’t care bits, and the reading of data.
When the end of a buffer is reached, the device will continue reading back at the beginning of the buffer. A low to
high transition on the CS
pin will terminate the read opera-
tion and tri-state the SO pin.
pin
pin will
pin
3
MAIN MEMORY PAGE TO BUFFER TRANSFER: A page
of data can be transferred from the main memory to either
buffer 1 or buffer 2. An 8-bit opcode, 53H for buffer 1 and
55H for buffer 2, is followed by one reserved bit, 13
address bits (PA12-PA0) which specify the page in main
memory that is to be transferred, and 10 don’t care bits.
The CS
pin must be low while toggling the SCK pin to load
the opcode, the address bits, and the don’t care bits from
the SI pin. The transfer of the page of data from the main
memory to the buffer will begin when the CS
pin transitions
from a low to a high state. During the transfer of a page of
data (t
), the status register can be read to determine
XFR
whether the transfer has been completed or not.
MAIN MEMORY PAGE TO BUFFER COMPARE: A page
of data in main memory can be compared to the data in
buffer 1 or buffer 2. An 8-bit opcode, 60H for buffer 1 and
61H for buffer 2, is followed by 24 address bits consisting of
one reserved bit, 13 address bits (PA12-PA0) which specify the page in the main memory that is to be compared to
the buffer, and 10 don't care bits. The loading of the
opcode and the address bits is the same as described previously. The CS
pin must be low while toggling the SCK pin
to load the opcode, the address bits, and the don't care bits
from the SI pin. On the low to high transition of the CS
pin,
the 528 bytes in the selected main memory page will be
compared with the 528 bytes in buffer 1 or buffer 2. During
this time (t
), the status register will indicate that the part
XFR
is busy. On completion of the compare operation, bit 6 of
the status register is updated with the result of the compare.
Program
BUFFER WRITE: Data can be shifted in from the SI pin
into either buffer 1 or buffer 2. To load data into either
buffer, an 8-bit opcode, 84H for buffer 1 or 87H for buffer 2,
is followed by 14 don't care bits and 10 address bits (BFA9BFA0). The 10 address bits specify the first byte in the
buffer to be written. The data is entered following the
address bits. If the end of the data buffer is reached, the
device will wrap around back to the beginning of the buffer.
Data will continue to be loaded into the buffer until a low to
high transition is detected on the CS
BUFFER TO MAIN MEMORY PAGE PROGRAM WITH
BUILT-IN ERASE: Data written into either buffer 1 or buffer
2 can be programmed into the main memory. An 8-bit
opcode, 83H for buffer 1 or 86H for buffer 2, is followed by
one reserved bit, 13 address bits (PA12-PA0) that specify
the page in the main memory to be written, and 10 additional don't care bits. When a low to high transition occurs
on the CS
pin, the part will first erase the selected page in
pin.
main memory to all 1s and then program the data stored in
the buffer into the specified page in the main memory. Both
the erase and the programming of the page are internally
self timed and should take place in a maximum time of t
EP
During this time, the status register will indicate that the
part is busy.
BUFFER TO MAIN MEMORY PAGE PROGRAM WITHOUT BUILT-IN ERASE: A previously erased page within
main memory can be programmed with the contents of
either buffer 1 or buffer 2. An 8-bit opcode, 88H for buffer 1
or 89H for buffer 2, is followed by one reserved bit, 13
address bits (PA12-PA0) that specify the page in the main
memory to be written, and 10 additional don’t care bits.
When a low to high transition occurs on the CS
pin, the part
will program the data stored in the buffer into the specified
page in the main memory. It is necessary that the page in
main memory that is being programmed has been previously erased. The programming of the page is internally
self timed and should take place in a maximum time of t
During this time, the status register will indicate that the
part is busy.
PAGE ERASE: The optional Page Erase command can be
used to individually erase any page in the main memory
array allowing the Buffer to Main Memory Page Program
without Built-In Erase command to be utilized at a later
time. To perform a Page Erase, an opcode of 81H must be
loaded into the device, followed by one reserved bit, 13
address bits (PA12-PA0), and 10 don’t care bits. The 13
address bits are used to specify which page of the memory
array is to be erased. When a low to high transition occurs
on the CS
pin, the part will erase the selected page to 1s.
The erase operation is internally self-timed and should take
place in a maximum time of t
. During this time, the status
PE
register will indicate that the part is busy.
BLOCK ERASE: A block of eight pages can be erased at
one time allowing the Buffer to Main Memory Page Program without Built-In Erase command to be utilized to
reduce programming times when writing large amounts of
data to the device. To perform a Block Erase, an opcode of
50H must be loaded into the device, followed by one
reserved bit, 10 address bits (PA12-PA3), and 13 don’t
care bits. The 10 address bits are used to specify which
block of eight pages is to be erased. When a low to high
transition occurs on the CS
pin, the part will erase the
selected block of eight pages to 1s. The erase operation is
internally self-timed and should take place in a maximum
time of t
. During this time, the status register will indicate
BE
that the part is busy.
.
.
P
4
AT45DB321
AT45DB321
Block Erase Addressing
PA 12 PA 11 PA 10 PA 9 PA 8 PA 7 PA 6 PA 5 PA 4 PA 3 PA 2 PA 1 PA 0 Bl oc k
0 0 0 0000000XXX 0
0 0 0 0000001XXX 1
0 0 0 0000010XXX 2
0 0 0 0000011XXX 3
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1 1 1 1111100XXX1020
1 1 1 1111101XXX1021
1 1 1 1111110XXX1022
1 1 1 1111111XXX1023
MAIN MEMORY PAGE PROGRAM: This operation is a
combination of the Buffer Write and Buffer to Main Memory
Page Program with Built-In Erase operations. Data is first
shifted into buffer 1 or buffer 2 from the SI pin and then programmed into a specified page in the main memory. An 8bit opcode, 82H for buffer 1 or 85H for buffer 2, is followed
by one reserved bit and 23 address bits. The 13 most significant address bits (PA12-PA0) select the page in the
main memory where data is to be written, and the next 10
address bits (BFA9-BFA0) select the first byte in the buffer
to be written. After all address bits are shifted in, the part
will take data from the SI pin and store it in one of the data
buffers. If the end of the buffer is reached, the device will
wrap around back to the beginning of the buffer. When
there is a low to high transition on the CS
first erase the selected page in main memory to all 1s and
then program the data stored in the buffer into the specified
page in the main memory. Both the erase and the programming of the page are internally self timed and should take
place in a maximum of time t
register will indicate that the part is busy.
AUTO PAGE REWRITE: This mode is only needed if multiple bytes within a page or multiple pages of data are modified in a random fashion. This mode is a combination of two
operations: Main Memory Page to Buffer Transfer and
Buffer to Main Memory Page Program with Built-In Erase.
A page of data is first transferred from the main memory to
buffer 1 or buffer 2, and then the same data (from buffer 1
or buffer 2) is programmed back into its original page of
main memory. An 8-bit opcode, 58H for buffer 1 or 59H for
buffer 2, is followed by one reserved bit, 13 address bits
(PA12-PA0) that specify the page in main memory to be
rewritten, and 10 additional don't care bits. When a low to
high transition occurs on the CS
fer data from the page in main memory to a buffer and then
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program the data from the buffer back into same page of
main memory. The operation is internally self-timed and
should take place in a maximum time of t
. During this
EP
time, the status register will indicate that the part is busy.
If a sector is programmed or reprogrammed sequentially
page by page, then the programming algorithm shown in
Figure 1 is recommended. Otherwise, if multiple bytes in a
page or several pages are programmed randomly in a sector, then the programming algorithm shown in Figure 2 is
recommended.
STATUS REGISTER: The status register can be used to
determine the device’s ready/busy status, the result of a
Main Memory Page to Buffer Compare operation, or the
pin, the part will
device density. To read the status register, an opcode of
57H must be loaded into the device. After the last bit of the
opcode is shifted in, the eight bits of the status register,
starting with the MSB (bit 7), will be shifted out on the SO
pin during the next eight clock cycles. The five most-signifi-
. During this time, the status
EP
cant bits of the status register will contain device information, while the remaining three least-significant bits are
reserved for future use and will have undefined values.
After bit 0 of the status register has been shifted out, the
sequence will repeat itself (as long as CS
remains low and
SCK is being toggled) starting again with bit 7. The data in
the status register is constantly updated, so each repeating
sequence will output new data.
Ready/busy status is indicated using bit 7 of the status register. If bit 7 is a 1, then the device is not busy and is ready
to accept the next command. If bit 7 is a 0, then the device
is in a busy state. The user can continuously poll bit 7 of the
status register by stopping SCK once bit 7 has been output.
The status of bit 7 will continue to be output on the SO pin,
pin, the part will first trans-
and once the device is no longer busy, the state of SO will
change from 0 to 1. There are eight operations which can
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5
cause the device to be in a busy state: Main Memory Page
to Buffer Transfer, Main Memory Page to Buffer Compare,
Buffer to Main Memory Page Program with Built-In Erase,
Buffer to Main Memory Page Program without Built-In
Erase, Page Erase, Block Erase, Main Memory Page Program, and Auto Page Rewrite.
The result of the most recent Main Memory Page to Buffer
Compare operation is indicated using bit 6 of the status
register. If bit 6 is a 0, then the data in the main memory
page matches the data in the buffer. If bit 6 is a 1, then at
least one bit of the data in the main memory page does not
match the data in the buffer.
The device density is indicated using bits 5, 4, and 3 of the
status register. For the AT45DB321, the three bits are 1, 1,
and 0. The decimal value of these three binary bits does
not equate to the device density; the three bits represent a
combinational code relating to differing densities of Serial
DataFlash devices, allowing a total of eight different density
configurations.
Read/Program Mode Summary
The modes listed above can be separated into two groups
— modes which make use of the flash memory array
(Group A) and modes which do not make use of the flash
memory array (Group B).
Group A modes consist of:
1. Main Memory Page Read
2. Main Memory Page to Buffer 1 (or 2) Transfer
3. Main Memory Page to Buffer 1 (or 2) Compare
4. Buffer 1 (or 2) to Main Memory Page Program With
Built-In Erase
5. Buffer 1 (or 2) to Main Memory Page Program Without Built-In Erase
6. Page Erase
7. Block Erase
8. Main Memory Page Program
9. Auto Page Rewrite
Group B modes consist of:
1. Buffer 1 (or 2) Read
2. Buffer 1 (or 2) Write
3. Status Register Read
If a Group A mode is in progress (not fully completed) then
another mode in Group A should not be started. However,
during this time in which a Group A mode is in progress,
modes in Group B can be started.
This gives the Serial DataFlash the ability to virtually
accommodate a continuous data stream. While data is
being programmed into main memory from buffer 1, data
can be loaded into buffer 2 (or vice versa). See application
note AN-4 (“Using Atmel’s Serial DataFlash”) for more
details.
HARDWARE PAGE WRITE PROTECT: If the WP
held low, the first 256 pages of the main memory cannot be
reprogrammed. The only way to reprogram the first 256
pages is to first drive the protect pin high and then use the
program commands previously mentioned. The WP
internally pulled high; therefore, connection of the WP
not necessary if this pin and feature will not be utilized.
However, it is recommended that the WP
externally whenever possible.
RESET
the operation in progress and reset the internal state
machine to an idle state. The device will remain in the reset
condition as long as a low level is present on the RESET
pin. Normal operation can resume once the RESET pin is
brought back to a high level.
The device incorporates an internal power-on reset circuit,
so there are no restrictions on the RESET
power-on sequences. The RESET
pulled high; therefore, connection of the RESET
necessary if this pin and feature will not be utilized. However, it is recommended that the RESET
externally whenever possible.
READY/BUSY
low when the device is busy in an internally self-timed operation. This pin, which is normally in a high state (through an
external pull-up resistor), will be pulled low during programming operations, compare operations, and during page-tobuffer transfers.
The busy status indicates that the Flash memory array and
one of the buffers cannot be accessed; read and write
operations to the other buffer can still be performed.
: A low state on the reset pin (RESET) will terminate
: This open drain output pin will be driven
pin be driven high
pin is also internally
pin be driven high
pin is
pin is
pin is
pin during
pin is not
Power On/Reset State
When power is first applied to the device, or when recovering from a reset condition, the device will default to SPI
mode 3. In addition, the SO pin will be in a high impedance
state, and a high to low transition on the CS
required to start a valid instruction. The SPI mode will be
automatically selected on every falling edge of CS
pling the inactive clock state.
pin will be
by sam-
Status Register Format
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
RDY/BUSY
6
COMP110XXX
AT45DB321
Absolute Maximum Ratings*
Temperature Under Bias................................ -55°C to +125°C
Storage Temperature..................................... -65°C to +150°C
All Input Voltages
(including NC Pins)
with Respect to Ground...................................-0.6V to +6.25V
All Output Voltages
with Respect to Ground.............................-0.6V to V
+ 0.6V
CC
DC and AC Operating Range
AT45DB321
*NOTICE: Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and
functional operation of the device at these or any
other conditions beyond those indicated in the
operational sections of this specification is not
implied. Exposure to absolute maximum rating
conditions for extended periods may affect device
reliability.
AT45DB321
Operating Temperature
(Case)
V
Power Supply
CC
Note: 1. After power is applied and VCC is at the minimum specified data sheet value, the system should wait 20 ms before an oper-
(1)
ational mode is started.
Com. 0°C to 70°C
Ind. -40°C to 85°C
2.7V to 3.6V
7
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