1. Features
•
Write Protect Pin for Hardware Data Protection
•
•
•
•
•
•
•
•
•
•
– Utilizes Different Array Protection Compared to the AT24C02B
Low-voltage and Standard-voltage Operation
– 1.8 (V
CC
= 1.8V to 5.5V)
Internally Organized 256 x 8 (2K)
Two-wire Serial Interface
Schmitt Trigger, Filtered Inputs for Noise Suppression
Bidirectional Data Transfer Protocol
1 MHz (5V) and 400 kHz (1.8V, 2.5V, 2.7V) Clock Rate
8-byte Page
Partial Page Writes Allowed
Self-timed Write Cycle (5 ms Max)
High Reliability
– Endurance: One Million Write Cycles
– Data Retention: 100 Years
8-lead PDIP, 8-lead JEDEC SOIC and 8-lead TSSOP Packages
Die Sales: Wafer Form, Tape and Reel, and Bumped Wafers
Two-wire Serial
EEPROM
2K (256 x 8)
•
•
AT24HC02B
Not Recommended
for New Design.
Replaced by
AT24HC02C.
2. Description
The AT24HC02B provides 2048 bits of serial electrically erasable and programmable
read-only memory (EEPROM) organized as 256 words of 8 bits each. The device is
optimized for use in many industrial and commercial applications where low-power
and low-voltage operation are essential. The AT24HC02B is available in space-saving
8-lead PDIP, 8-lead JEDEC SOIC and 8-lead TSSOP packages and is accessed via a
two-wire serial interface. In addition, the entire family is available in 1.8V (1.8V to
5.5V) version.
Table 2-1.
Pin Name
A0–A2
SDA
SCL
WP
Pin Configuration
Function
Address Inputs
Serial Data
Serial Clock Input
Write Protect
A0
A1
A2
GND
1
2
3
4
8
7
6
5
VCC
WP
SCL
SDA
8-lead TSSOP
8-lead PDIP
A0
A1
A2
GND
1
2
3
4
8
7
6
5
VCC
WP
SCL
SDA
8-lead SOIC
A0
A1
A2
GND
1
2
3
4
8
7
6
5
VCC
WP
SCL
SDA
Rev. 5134E–SEEPR–3/08
Absolute Maximum Ratings*
Operating Temperature
55C
to +125C
Storage Temperature
65C
to +150C
Voltage on Any Pin
with Respect to Ground
1.0V
to +7.0V
Maximum Operating Voltage .......................................... 6.25V
DC Output Current........................................................ 5.0 mA
*NOTICE:
Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent dam-
age 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.
Figure 2-1.
VCC
GND
WP
SCL
SDA
Block Diagram
START
STOP
LOGIC
LOAD
DEVICE
ADDRESS
COMPARATOR
A
2
A
1
A
0
R/W
COMP
SERIAL
CONTROL
LOGIC
EN
H.V. PUMP/TIMING
DATA RECOVERY
INC
LOAD
DATA WORD
ADDR/COUNTER
X DEC
EEPROM
Y DEC
SERIAL MUX
D
IN
D
OUT
D
OUT
/ACK
LOGIC
2
AT24HC02B
5134E–SEEPR–3/08
AT24HC02B
3. Pin Description
SERIAL CLOCK (SCL):
The SCL input is used to positive edge clock data into each EEPROM
device and negative edge clock data out of each device.
SERIAL DATA (SDA):
The SDA pin is bidirectional for serial data transfer. This pin is open-
drain driven and may be wire-ORed with any number of other open-drain or open collector
devices.
DEVICE/PAGE ADDRESSES (A2, A1, A0):
The A2, A1 and A0 pins are device address inputs
that must be hardwired for the AT24HC02B. As many as eight 2K devices may be addressed on
a single bus system. (Device addressing is discussed in detail under
Device Addressing,
page
8).
WRITE PROTECT (WP):
The AT24HC02B has a WP pin that provides hardware data protec-
tion. The WP pin allows normal read/write operations when connected to ground (GND). When
the WP pin is connected to V
CC
, the write protection feature is enabled and operates as shown.
Table 3-1.
Write Protect
Part of the Array Protected
WP Pin Status
At V
CC
At GND
24HC02B
Upper Half (1K) Array
Normal Read/Write Operations
3
5134E–SEEPR–3/08
4. Memory Organization
AT24HC02B, 2K SERIAL EEPROM:
The 2K is internally organized with 32 pages of 8 bytes
each. Random word addressing requires an 8-bit data word address.
Table 4-1.
Pin Capacitance
(1)
Applicable over recommended operating range from T
AI
= 25C, f = 1.0 MHz, V
CC
= +1.8V
Symbol
C
I/O
C
IN
Note:
Test Condition
Input/Output Capacitance (SDA)
Input Capacitance (A
0
, A
1
, A
2
, SCL)
1. This parameter is characterized and is not 100% tested.
Max
8
6
Units
pF
pF
Conditions
V
I/O
= 0V
V
IN
= 0V
Table 4-2.
DC Characteristics
Applicable over recommended operating range from: T
AI
=
40C
to +85C, V
CC
= +1.8V to +5.5V (unless otherwise noted)
Symbol
V
CC1
V
CC2
V
CC3
V
CC4
I
CC
I
CC
I
SB1
I
SB2
I
SB3
I
SB4
I
LI
I
LO
V
IL
V
IH
V
OL2
V
OL1
Note:
Parameter
Supply Voltage
Supply Voltage
Supply Voltage
Supply Voltage
Supply Current V
CC
= 5.0V
Supply Current V
CC
= 5.0V
Standby Current V
CC
= 1.8V
Standby Current V
CC
= 2.5V
Standby Current V
CC
= 2.7V
Standby Current V
CC
= 5.0V
Input Leakage Current
Output Leakage Current
Input Low Level
(1)
Input High Level
(1)
Output Low Level V
CC
= 3.0V
Output Low Level V
CC
= 1.8V
I
OL
= 2.1 mA
I
OL
= 0.15 mA
READ at 100 kHz
WRITE at 100 kHz
V
IN
= V
CC
or V
SS
V
IN
= V
CC
or V
SS
V
IN
= V
CC
or V
SS
V
IN
= V
CC
or V
SS
V
IN
= V
CC
or V
SS
V
OUT
= V
CC
or V
SS
0.6
V
CC
x 0.7
Test Condition
Min
1.8
2.5
2.7
4.5
0.4
2.0
0.6
1.4
1.6
8.0
0.10
0.05
Typ
Max
5.5
5.5
5.5
5.5
1.0
3.0
3.0
4.0
4.0
18.0
3.0
3.0
V
CC
x 0.3
V
CC
+ 0.5
0.4
0.2
Units
V
V
V
V
mA
mA
µA
µA
µA
µA
µA
µA
V
V
V
V
1. V
IL
min and V
IH
max are reference only and are not tested.
4
AT24HC02B
5134E–SEEPR–3/08
AT24HC02B
Table 4-3.
AC Characteristics
Applicable over recommended operating range from T
AI
=
–
40C to +85C, V
CC
= +1.8V to +5.5V, CL = 1 TTL Gate and
100 pF (unless otherwise noted)
1.8, 2.5, 2.7
Symbol
f
SCL
t
LOW
t
HIGH
t
I
t
AA
t
BUF
t
HD.STA
t
SU.STA
t
HD.DAT
t
SU.DAT
t
R
t
F
t
SU.STO
t
DH
t
WR
Endurance
(1)
Note:
Parameter
Clock Frequency, SCL
Clock Pulse Width Low
Clock Pulse Width High
Noise Suppression Time
Clock Low to Data Out Valid
Time the bus must be free before a new
transmission can start
Start Hold Time
Start Setup Time
Data In Hold Time
Data In Setup Time
Inputs Rise Time
(1)
Inputs Fall Time
(1)
Stop Setup Time
Data Out Hold Time
Write Cycle Time
5.0V, 25C, Byte Mode
0.6
50
5
1 Million
0.1
1.2
0.6
0.6
0
100
0.3
300
.25
50
5
1.2
0.6
50
0.9
0.05
0.5
0.25
0.25
0
100
0.3
100
Min
Max
400
0.4
0.4
40
0.55
5.0-volt
Min
Max
1000
Units
kHz
µs
µs
ns
µs
µs
µs
µs
µs
ns
µs
ns
µs
ns
ms
Write Cycles
1. This parameter is ensured by characterization only.
5
5134E–SEEPR–3/08
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