– 5.0 (VCC = 4.5V to 5.5V)
– 2.7 (VCC = 2.7V to 5.5V)
– 1.8 (VCC = 1.8V to 3.6V)
•
2.1 MHz Clock Rate
•
32-Byte Page Mode
•
Block Write Protection
– Protect 1/4, 1/2, or Entire Array
•
Write Protect (WP) Pin and Write Disable Instructions for
Both Hardware and Software Data Protection
•
Self-Timed Write Cycle (5 ms Typical)
•
High Reliability
– Endurance: 1 Million Write Cycles
– Data Retention: 100 Years
– ESD Protection: >4000V
•
Automotive Grade and Extended Temperature Devices Available
•
8-Pin PDIP, JEDEC SOIC, and 14-Pin and 20-Pin TSSOP Packages
SPI Serial
EEPROMs
8K (1024 x 8)
16K (2048 x 8)
32K (4096 x 8)
Description
The AT25080/160/320/640 provides 8192/16384/32768/65536 bits of serial electrically erasable programmable read only memory (EEPROM) organized as
1024/2048/4096/8192 words of 8 bits each. The device is optimized for use in many
industrial and commercial applications where low power and low voltage operation
(continued)
Pin Configuration
Pin NameFunction
CS
Chip Select
SCKSerial Data Clock
SISerial Data Input
SOSerial Data Output
GNDGround
V
CC
WP
Power Supply
Write Protect
HOLDSuspends Serial Input
NCNo Connect
DCDon’t Connect
8-Pin PDIP
1
CS
2
SO
3
WP
4
GND
14-Lead TSSOP
CS
1
SO
2
NC
3
NC
4
NC
5
WP
6
GND
7
VCC
8
HOLD
7
SCK
6
SI
5
14
VCC
13
HOLD
12
NC
11
NC
10
NC
9
SCK
8
SI
8-Pin SOIC
1
CS
2
SO
3
WP
4
GND
20-Lead TSSOP*
1
NC
2
CS
3
SO
4
SO
5
NC
6
NC
7
WP
8
GND
9
DC
10
NC
VCC
8
HOLD
7
SCK
6
SI
5
20
NC
19
VCC
18
HOLD
17
HOLD
16
NC
15
NC
14
SCK
13
SI
12
DC
11
NC
64K (8192 x 8)
AT25080
AT25160
AT25320
AT25640
*Pins 3, 4 and 17, 18 are internally connected for 14-lead TSSOP socket compatibility.
Rev. 0675C–08/98
1
Page 2
are essential. The AT25080/160/320/640 is available in
space saving 8-pin PDIP, JE DEC SOIC, and 14-pin and
20-pin TSSOP packages.
The AT25080/160/320/640 is enabled through the Chip
Select pin (CS
sisting of Serial Data Input (SI), Serial Data Output (SO),
and Serial Clock (SCK). All programmi ng cycles are c ompletely self-timed, and no separate E RASE cycle is
required before WRITE.
) and accessed via a 3-wire interface con-
Absolute Maximum Ratings*
Operating Temperature.................................. -55°C to +125°C
Storage Temperature..................................... -65°C to +150°C
Voltage on Any Pin
with Respect to Ground.....................................-1.0V to +7.0V
Maximum Operating Voltage........................................... 6.25V
DC Output Current........................................................5 .0 mA
Block Diagram
BLOCK WRITE protection is enabled by programming the
status register with one of four blocks of write protection.
Separate program ena ble and p rogr am di sabl e in str uc tions
are provided for additional data protection. Hardware data
protection is provided via the WP
inadvertent write attempts to the status register. The HOLD
pin may be used to suspend an y serial communi cation
without resetting the serial sequence.
*NOTICE:Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent damage to the dev ice . This is a s tress rating only an d
functional oper ation of the de vi ce 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 f or e xtended periods ma y af fect de vice
reliability .
pin to protect against
2
AT25080/160/320/640
Page 3
AT25080/160/320/640
Pin Capacitance
(1)
Applicable over recommended operating range from TA = 25°C, f = 1.0 MHz, VCC = +5.0V (unless otherwise noted).
Note:1. This parameter is characterized and is not 100% tested.
DC Characteristics
Applicable over recommended operating range from: TAI = -40°C to +85°C, VCC = +1.8V to +5.5V, TAC = 0°C to +70°C,
= +1.8V to +5.5V (unless otherwise noted).
V
CC
Symbol ParameterTest Condition MinTypMaxUnits
V
CC1
V
CC2
V
CC3
I
CC1
I
CC2
I
SB1
I
SB2
I
SB3
I
IL
I
OL
(1)
V
IL
(1)
V
IH
V
OL1
V
OH1
V
OL2
V
OH2
Note:1. V
Supply Voltage1.83.6V
Supply Voltage2.75.5V
Supply Voltage4.55.5V
Supply Current
Supply Current
Standby Current
Standby Current
Standby Current
Input Leakage
Output Leakage
Input Low Voltage-0.6
Input High Voltage
Output Low Voltage
Output High Voltage
Output Low Voltage
Output High VoltageI
min and VIH max are reference only and are not tested.
IL
V
= 5.0V at 1 MHz, SO = Open
CC
V
= 5.0V at 2 MHz, SO = Open
CC
V
= 1.8V, CS = V
CC
V
= 2.7V, CS = V
CC
V
= 5.0V, CS = V
CC
V
= 0V to V
IN
V
= 0V to V
IN
4.5V ≤ V
1.8V ≤ V
CC
CC
≤
≤
CC
,
T
CC
5.5V
3.6V
AC
CC
CC
CC
= 0°C to 70°C
= 3.0 mA
I
OL
I
= -1.6 mAV
OH
= 0.15 mA
I
OL
= -100 µAV
OH
0.20.5
0.52.0
-3.03.0
-3.03.0
V
CC
V
x 0.7V
CC
- 0.8
CC
- 0.2 V
CC
CC
3.0mA
5.0mA
0.1
µ
µ
µ
µ
µ
x 0.3
+ 0.5
V
V
0.4V
V
0.2V
A
A
A
A
A
3
Page 4
AC Characteristics
Applicable over recommended operating range from TA = -40°C to +85°C, VCC = As Specified,
CL = 1 TTL Gate and 100 pF (unless otherwise noted).
SymbolParameterVoltageMinMaxUnits
f
SCK
SCK Clock Frequency
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
0
0
0
2.1
2.1
0.5
MHz
t
RI
t
FI
t
WH
t
WL
t
CS
t
CSS
t
CSH
t
SU
Input Rise Time
Input Fall Time
SCK High Time
SCK Low Time
CS High Time
CS Setup Time
CS Hold Time
Data In Setup Time
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
200
200
800
200
200
800
250
250
1000
250
250
1000
250
250
1000
50
50
100
2
2
2
2
2
2
ns
µ
µ
ns
ns
ns
ns
ns
s
s
4.5 - 5.5
t
H
Data In Hold Time
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
t
HD
Hold Setup Time
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
t
CD
Hold Hold Time
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
t
V
Output Valid
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
t
HO
Output Hold Time
2.7 - 5.5
1.8 - 3.6
4
AT25080/160/320/640
50
50
100
100
100
400
200
200
400
0
0
0
0
0
0
200
200
800
ns
ns
ns
ns
Page 5
AT25080/160/320/640
AC Characteristics (Continued)
Applicable over recommended operating range from TA = -40°C to +85°C, VCC = As Specified,
CL = 1 TTL Gate and 100 pF (unless otherwise noted).
SymbolParameterVoltageMinMaxUnits
4.5 - 5.5
t
LZ
t
HZ
t
DIS
t
WC
Endurance
Note:1. This parameter is characterized and is not 100% tested.
(1)
Hold to Output Low Z
Hold to Output High Z
Output Disable Time
Write Cycle Time
5.0V, 25°C, Page Mode1MWrite Cycles
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
4.5 - 5.5
2.7 - 5.5
1.8 - 3.6
0
0
0
100
100
100
100
100
100
250
250
1000
5
10
20
ns
ns
ns
ms
5
Page 6
Serial Interface Description
MASTER:
SLAVE:
input, the AT25080/160/320/640 always operates as a
slave.
TRANSMITTER/RECEIVER:
has separate pins designated for data transmission (SO)
and reception (SI).
MSB:
mitted and received.
SERIAL OP-CODE:
going low, the first byte will be receiv ed. This byte co ntains
the op-code that defines the operations to be performed.
INVA LID OP-CODE:
data will be shifted into the AT25080/16 0/320/640 , and the
serial output pin (SO) will remain in a high impedance state
until the falling edge of CS
tialize the serial communication.
CHIP SELECT:
when the CS
data will not be accepte d via th e SI pin, and the ser ial output pin (SO) will remain in a high impedance state.
HOLD:
pin to select the AT25080/160/320/640. When the device is
selected and a se ri al se que nce is un derwa y, HOLD
used to pause the se rial communica tion with the master
device without resetting the serial sequence. To pause, the
HOLD
resume serial communication, the HOLD
high while the SCK pin is low (SCK may still toggle during
HOLD
is in the high impedance state.
WRITE PROTECT:
normal read/ write opera tions when he ld high. Wh en the
WP pin is brought low an d WPE N bit is “1”, al l write o pera-
The device that generates the serial clock.
Because the Serial Clock pi n (SCK) is always a n
The AT25080/160/320/640
The Most Significant Bit (M SB) is th e first bi t trans-
After the device is selected with CS
If an invalid op-code is received, no
is detected again. This will reini-
The AT25080/160/320/640 is selected
pin is low . When the de vice is no t sele cted,
The HOLD
pin must be brought low while the SCK pin is low. To
). Inputs to the SI pin will be ignored while the SO pin
pin is us ed in conju nctio n wit h the CS
can be
pin is brought
The write protect pi n (WP
) will allow
tions to the sta tus register are inhibited . WP
while CS
ter. If the internal write cycle has already been initiated, WP
going low will have no effect on any write operation to the
status register. The WP
WPEN bit in the status r egister is "0". T his will allow t he
user to ins tall t he AT25 080/16 0/320/6 40 in a sy stem w ith
the WP
status regi ste r. All WP
WPEN bit is set to “1”.
is still low will interrupt a wr ite to the status r egis-
pin function is blocked when the
pin tied to ground and still be able to write to the
pin functions are enabled when the
going low
SPI Serial Interface
6
AT25080/160/320/640
Page 7
AT25080/160/320/640
Functional Description
The AT25080/160/32 0/640 is desi gned to i nterfac e di rectly
with the synchronous serial peripheral interface (SPI) of the
6805 and 68HC11 series of microcontrollers.
The AT25080/160/320/640 utilizes an 8 bit instruction register. The list of instructions and their operation codes are
contained in Table 1. All instructions, addresses, and data
are transferred with the MSB first and start with a high-tolow CS transition.
Table 1.
Instruction
Name
WREN0000 X110Set Write Enable Latch
WRDI0000 X100Reset Write Enable Latch
RDSR0000 X101Read Status Register
WRSR0000 X001Write Status Register
READ0000 X011Read Data from Memory Array
WRITE0000 X010Write Data to Memory Array
WRITE ENABLE (WREN):
write disable state when V
instructions mus t t here fo re be p reced ed b y a Wr ite Enab le
instruction.
WRITE DISABLE (WRDI):
inadvertent writes, the Wr it e Dis able i nst ru cti on disabl es all
programming modes. The WRDI ins tructio n is ind ependen t
of the status of the WP
READ STATUS REGISTER (RDSR):
Register instruction provides access to the status register.
The READY/BUSY an d Write Enable sta tus of th e devic e
can be determined by the RDSR instruction. Similarly, the
Block Write Pr otec tion bits i ndic ate th e exten t o f prote ctio n
employed. These bits are set by using the WRSR instru ction.
Table 2.
WPENXXXBP1BP0WENRDY
Instruction Set for the AT25080/160/320/640
Instruction
FormatOperation
The device will power u p in th e
is applied. All programming
CC
To protect the device against
pin.
The Read Status
Status Register Format
Bit 7Bit 6Bit 5Bit 4Bit 3Bi t 2Bit 1Bit 0
Table 3.
BitDefinition
Bit 0 (RDY
Bit 1 (WEN)
Bit 2 (BP0)See Table 3.
Bit 3 (BP1)See Table 3.
Bits 4-6 are 0s when device is not in an internal write cycle.
Bit 7 (WPEN) See Table 4.
Bits 0-7 are 1s during an internal write cycle.
WRITE STATUS REGISTER (WRSR):
Read Status Register Bit Definition
)
Bit 0 = 0 (RDY
0 = 1 indicates the write cycle is in progress.
Bit 1= 0 indicates the device is not WRITE
ENABLED. Bit 1 = 1 indicates the de vice is WRITE
ENABLED.
) indicates the device is READY. Bit
The WRSR instruction allows the user to select one of four levels of protection. The AT25080/160/320/640 is divided into four array
segments. One quarter ( 1/4), one half ( 1/2), or all of the
memory segments can be protected. Any of the data within
any selected segment will therefore be READ only. The
block write prot ection le vels and corr espondi ng stat us register control bits are shown in Table 4.
The three bits, BP0, BP1, and WPEN are nonvolatile cells
that have the same pro perties and functi ons as the regul ar
memory cells (e.g. WREN, t
Table 4.
Level
000NoneNoneNoneNone
1(1/4)01
2(1/2)10
3(All)11
Block Write Protect Bits
Status
Register
BitsArra y Addresses Protected
BP1BP0AT25080AT25160AT25320AT25640
0300
-03FF
0200
-03FF
0000
-03FF
, RDSR).
WC
-07FF
-07FF
-07FF
0600
0400
0000
0C00
-0FFF
0800
-0FFF
0000
-0FFF
1800
-1FFF
1000
-1FFF
0000
-1FFF
The WRSR instruction also allows the user to enable or
disable the write protect (WP
) pin through the use of the
Write Protect Enable (WPEN) bit. Hardware write protection is ena bl e d wh en t h e W P
pin is low and the WPEN bit is
“1”. Hardware write protection is disabled when either the
pin is high or the WPEN bit is “0”. When the device is
WP
hardware write protected, writes to the Status Register,
including the Bloc k Protec t bits and the WPEN bi t, and the
block-protected sec tions in the memor y arra y are disab led.
7
Page 8
Writes are only allowed to sections of the memory which
are not block-protected.
Reading the
AT25080/160/320/640 via the SO (Serial Output) pin
requires the follo win g seque nce. After the CS
line is pulled
low to select a device, the READ op-code is transmitted via
the SI line followed by the byte address to be read (A15-A0,
Refer to Table 6). Upon completion, any data on the SI line
will be ignored. The data (D7-D0) at the specified address
is then shifted out onto the SO line. If only one byte is to be
read, the CS
line should be driven high after the da ta
comes out. The READ sequence can be continued since
the byte address is automatically incremented and data will
continue to be shifted out. When the highest address is
reached, the addr ess counter will roll over to th e lowest
address allowing the ent ire memo ry to be read in one co ntinuous READ cycle.
WRITE SEQUENCE (WRITE):
In order to program the
AT25080/160/320/640, t wo sep arate instr uctions m ust be
executed. First, the device
must be write enabled
via the
Write Enable (WREN) Instruction. Then a Write (WRITE)
Instruction may be executed. Also, the address of the
memory location(s) to be p rogramm ed must be out side th e
protected address field location selected by the Block Write
Protection Level. During an internal write c ycle, all commands will be ignored except the RDSR instruction.
A Write Instruc tion r equires the foll owing s equence. After
the CS
line is pulled low to select the device, the WRITE
op-code is transmitted via the S I line follo wed by the byte
address (A15-A0) and the data (D7- D0) to be pr ogramme d
(Refer to Table 6). Programming will start after the CS
is brought high. (The LOW to High transition of the CS
pin
pin
must occur during the SCK low time immediately after
clocking in the D0 (LSB) data bit.
The READY/BUSY status of the devic e can be determine d
by initiating a READ STATUS REGISTER (RDSR) Instruction. If Bit 0 = 1, the WRITE cycle is still in progress. If Bit 0
= 0, the WRITE cycle has ended. Only the READ STATUS
REGISTER instruction is enabled during the WRITE programming cycle.
The AT25080/160/ 320/640 i s capable of a 32 -byte P AGE
WRITE operation. After each by te of data is receiv ed, the
five low order address bits are internally incremented by
one; the high order bits of the address will remain constant.
If more than 32-bytes of data are transmitted, the address
counter will roll over and the previously written data will be
overwritten. The AT25080/160/320/640 is automatically
returned to the write disable state at the completion o f a
WRITE cycle.
NOTE:
If the device is not Write enabled (WREN), the
device will igno re the Wr it e instruction and wil l r etu rn to th e
standby state, when CS
is brought high. A new CS falli ng
edge is required to re-initiate the serial communication.