TECHNICAL DATA
4K/8K 2.5V CMOS Serial EEPROMs
DESCRIPTION
IN24LC04B/08B
IN24LC04B/08B is a 4K-or 8K-bit Electrically Erasable PROM. The device is organized as two or four blocks of 256 x
8 bit memory with a two wire serial interface. Low voltage design permits operation down to 2.5 volts with standby and
active currents of only 5µA and 1mA respectively. The IN24LC04B/08B also has a page-write capability for up to 16
bytes of data. The IN24LC04B/08B is available in the standard 8-pin DIP.
FEATURES
• Single supply with operation down to 2.5V
• Low power CMOS technology
- 1 mA active current typical
- 10
µA
standby current typical at 5.5V
- 5
µA
standby current typical at 3.0V
• Organized as two or four blocks of 256 bytes (2x256x8) and
(4x256x8)
• Two wire serial interface bus, I
2
C compatible
• Schmitt trigger, filtered inputs for noise suppression
• Output slope control to eliminate ground bounce
• 100 kHz (2.5V) and 400 kHz (5V) compatibility
• Self-timed write cycle (including auto-erase)
• Page-write buffer for up to 16 bytes
• 2 ms typical write cycle time for page-write
• Hardware write protect for entire memory
• Can be operated as a serial ROM
• Factory programming (QTP) available
• ESD protection > 4,000V
• 1,000,000 ERASE/WRITE cycles guaranteed*
• Data retention > 200 years
• 8-pin DIP
• Temperature range -40 to +85
o
C
VCC
AO, A1, A2
+2.5V to 5.5V Power Supply
No Internal Connection
Name
Vss
SDA
SCL
WP
PACKAGE
T
A
= -40 ... +85
°C
PINNING
Function
Ground
Serial Address/Data I/O
Serial Clock
Write Protect Input
Pin Connection
A0
A1
A2
Vss
1
2
3
4
8
7
6
5
Vcc
WP
SCL
SDA
1
IN24LC04B/08B
Figure 1. Representative Block Diagram
ELECTRICAL CHARACTERISTICS
Maximum Ratings*
Parameter
V
CC
All inputs and outputs w.r.t.Vss
Storage temperature
Ambient temp. with power applied
Soldering temperature of leads (10 seconds)
ESD protection on all pins
Value
7.0 V
-0.3V to Vcc + 1.0V
-65
o
C to +150
o
C
-40 to +85
o
C
+300
o
C
> 4 kV
DC CHARACTERISTICS
Vcc = +2.5V to +5.5V Commercial: Tamb = -40to +85
Parameter
Symbol
Min
WP, SCL and SDA pins:
0.7V
CC
High level input voltage
V
lH
-
V
IL
Low level input voltage
V
HYS
0.05V
CC
Hysteresis of Schmitt trigger inputs
-
V
OL
Low level output voltage
Input leakage current
I
LI
-10
Output leakage current
I
LO
-10
Pin capacitance (all inputs/outputs)
C
IN
-
C
OUT
Operating current
I
CC
WRITE
-
I
CC
READ
-
Standby current
I
CCS
-
-
Max
-
0.3V
CC
-
0.40
10
10
10
3
1
30
100
Units
V
V
V
V
µA
µA
pF
mA
mA
µA
µA
Mode
Note 1
I
OL
=
3.0mA, V
CC
= 2.5V
V
lN
=0.1V to V
CC
V
OUT
=0.1V to V
CC
V
CC
= 5.0V (Note 1)
Tamb =25
o
C, Fclk =1MHz
V
CC
= 5.5V SCL = 400kHz
SDA=SCL=V
CC
=3.0V,
SDA=SCL=V
CC
=5.5V
2
IN24LC04B/08B
Figure 2. Bus timing Start/Stop
AC CHARACTERISTICS
Parameter
Clock frequency
Clock high time
Clock low time
SDA and SCL rise time
SDA and SCL fall time
START condition hold time
START condition setup time
T
SU:STA
Data input hold time
Data input setup time
STOP condition setup time
Output valid from clock
Bus free time
Output fall time from V
IH
min
to V
IL
max
Input filter spike suppres-sion
(SDA & SCL pins)
Write cycle time
T
HD:DAT
T
SU:DAT
T
SU:STO
T
AA
T
BUF
T
OF
T
SP
T
WR
4700
0
250
4000
-
4700
-
-
-
-
-
-
-
3500
-
250
50
10
600
0
100
600
-
1300
20+0.1C
B
-
-
-
-
-
-
900
-
250
50
10
ns
ns
ns
ns
ns
ns
ns
ns
ms
Symbol
F
CLK
T
HIGH
T
LOW
T
R
T
F
T
HD:STA
STANDARD
MODE
Vcc = 4.5 - 5.5V
FAST MODE
Min
-
4000
4700
-
-
4000
Max
100
-
-
1000
300
-
Min
-
600
1300
-
-
600
Max
400
-
-
300
300
-
Units Remarks
kHz
ns
ns
ns Note 2
ns Note 2
ns
After this period the
first clock pulse is
generated
Only relevant for
repeated START
condition
Note 1
Time the bus must be
free before a new
transmission can start
Note2,
C
B
≤100pF
Note 3
Byte or Page
mode
Note 1: As a transmitter, the device must provide an internal minimum delay time to bridge the undefined
region (minimum 300 ns) of the falling edge of SCL to avoid unintended generation of START or
STOP conditions.
Note 2: Not 100% tested. C
B
=
total capacitance of one bus line in pF.
Note 3: The combined T
SP
and V
HYS
specifications are due to new Schmitt trigger inputs which provide
improved noise and spike suppression. This eliminates the need for a Ti specification for standard
operation.
3
IN24LC04B/08B
Figure 3. Bus timing Data
FUNCTIONAL DESCRIPTION
The IN24LC04B/08B supports a bidirectional two wire bus and data transmission protocol. A
device that sends data onto the bus is defined as transmitter, and a device receiving data as receiver.
The bus has to be controlled by a master device which generates the serial clock (SCL), controls the
bus access, and generates the START and STOP conditions, while the IN24LC04B/08B works as
slave. Both, master and slave can operate as transmitter or receiver but the master device
determines which mode is activated.
BUS CHARACTERISTICS
The following bus protocol has been defined:
Data transfer may be initiated only when the bus is not busy.
During data transfer, the data line must remain stable whenever the clock line is HIGH. Changes in
the data line while the clock line is HIGH will be interpreted as a START or STOP condition.
Accordingly, the following bus conditions have been defined (see Figure 4).
Bus not Busy (A)
Both data and clock lines remain HIGH.
Start Data Transfer (B)
A HIGH to LOW transition of the SDA line while the clock (SCL) is HIGH determines a START
condition. All commands must be preceded by a START condition.
Stop Data Transfer (C)
A LOW to HIGH transition of the SDA line while the clock (SCL) is HIGH determines a STOP
condition. All operations must be ended with a STOP condition.
Data Valid (D)
The state of the data line represents valid data when, after a START condition, the data line is stable
for the duration of the HIGH period of the clock signal.
The data on the line must be changed during the LOW period of the clock signal. There is one clock
pulse per bit of data.
Each data transfer is initiated with a START condition and terminated with a STOP condition. The
number of the data bytes transferred between the START and STOP conditions is determined by the
master device and is theoretically unlimited, although only the last sixteen will be stored when
doing a write operation. When an overwrite does occur it will replace data in a first in first out
fashion.
4
IN24LC04B/08B
Acknowledge
Each receiving device, when addressed, is obliged to generate an acknowledge after the reception of
each byte. The master device must generate an extra clock pulse which is associated with this
acknowledge bit.
Note:
The IN24LC04B/08B does not generate any acknowledge bits if an internal programming cycle is in
progress
The device that acknowledges, has to pull down the SDA line during the acknowledge clock pulse
in such a way that the SDA line is stable LOW during the HIGH period of the acknowledge related
clock pulse. Of course, setup and hold times must be taken into account. A master must signal an
end of data to the slave by not generating an acknowledge bit on the last byte that has been clocked
out of the slave. In this case, the slave must leave the data line HIGH to enable the master to
generate the STOP condition.
Figure 4. Data Transfer Sequence on the serial bus
BUS CHARACTERISTICS
Device Addressing and Operation
A control byte is the first byte received following the start condition from the master device. The
control byte consists of a four bit control code, for the IN24LC04B/08B this is set as 1010 binary
for read and write operations. The next three bits of the control byte are the block select bits (B2,
B1, BO). B2 is a don't care for both the IN24LC04B and IN24LC08B; B1 is a don't care for the
IN24LC04B. They are used by the master device to select which of the two or four 256 word blocks
of memory are to be accessed. These bits are in effect the most significant bits of the word address.
The last bit of the control byte defines the operation to be performed. When set to one a read
operation is selected, when set to zero a write operation is selected. Following the start condition,
the IN24LC04B/08B monitors the SDA bus checking the device type identifier being transmitted,
upon a 1010 code the slave device outputs an acknowledge signal on the SDA line. Depending on
the state of the R/W bit, the IN24LC04B/ 08B will select a read or write operation.
Operation
Read
Write
Control Code
1010
1010
Block Select
Block Address
Block Address
R/W
1
0
5