Features

• Low Voltage and Standard Voltage Operation

– 5.0 (VCC = 4.5V to 5.5V)
– 2.7 (VCC = 2.7V to 5.5V)
– 2.5 (VCC = 2.5V to 5.5V)
– 1.8 (VCC = 1.8V to 5.5V)
• Internally Organized 128 x 8
• 2-Wire Serial Interface
• Bidirectional Data Transfer Protocol
• 100 kHz (1.8V, 2.5V, 2.7V) and 400 kHz (5V) Compatibility
•
•
4-Byte Page Write Mode
Self-Timed Write Cycle (10 ms max)
2-Wire Serial
• High Reliability
– Endurance: 1 Million Write Cycles EEPROM
– Data Retention: 100 Years
– ESD Protection: >3000V 1K (128 x 8)
• Automotive Grade and Extended Temperature Devices Available
• 8-Pin PDIP, 8-Pin MSOP, 8-Pin TSSOP and 8-Pin JEDEC SOIC Packages

Description
AT24C01
The AT24C01 provides 1024 bits of serial electrically erasable and programmable
read only memory (EEPROM) organized as 128 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 AT24C01 is available in space saving
8-pin PDIP, 8-pin MSOP, 8-pin TSSOP, and 8-pin JEDEC SOIC packages and is
accessed via a 2-wire serial interface. In addition, the entire family is available in 5.0V
(4.5V to 5.5V), 2.7V (2.7V to 5.5V), 2.5V (2.5V to 5.5V) and 1.8V (1.8V to 5.5V) ver-
sions.

8-Pin MSOP
Pin Configurations
8-Pin TSSOP
Pin Name Function
NC 1 8 VCC
NC No Connect
NC 2 7 TEST
SDA Serial Data NC 3 6 SCL
SCL Serial Clock Input GND 4 5 SDA 2-Wire, 1K
Test Test Input (GND or VCC)
Serial EEPROM
8-Pin PDIP 8-Pin SOIC

NC 1 8 VCC NC 1 8 VCC
NC 2 7 TEST NC 2 7 TEST
NC 3 6 SCL NC 3 6 SCL
GND 4 5 SDA GND 4 5 SDA

Rev. 0134C–07/98

1
Absolute Maximum Ratings*
Operating Temperature .................................. -55°C to +125°C *NOTICE: Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent dam-
Storage Temperature ..................................... -65°C to +150°C age to the device. This is a stress rating only and
functional operation of the device at these or any
Voltage on Any Pin other conditions beyond those indicated in the
with Respect to Ground .....................................-1.0V to +7.0V operational sections of this specification is not
implied. Exposure to absolute maximum rating
Maximum Operating Voltage........................................... 6.25V conditions for extended periods may affect
device reliability.
DC Output Current........................................................ 5.0 mA

Block Diagram

Pin Description Memory Organization

SERIAL CLOCK (SCL): The SCL input is used to positive AT24C01, 1K SERIAL EEPROM: Internally organized with
edge clock data into each EEPROM device and negative 128 pages of 1 byte each. The 1K requires a 7-bit data
edge clock data out of each device. word address for random word addressing.
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.

2 AT24C01
 AT24C01

Pin Capacitance
Applicable over recommended operating range from TA = 25°C, f = 1.0 MHz, VCC = +1.8V.
Symbol Test Condition Max Units Condition
CI/O Input/Output Capacitance (SDA) 8 pF VI/O = 0V
CIN Input Capacitance (A0, A1, A2, SCL) 6 pF VIN = 0V

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,
VCC = +1.8V to +5.5V (unless otherwise noted).
Symbol Parameter Test Condition Min Typ Max Units
VCC1 Supply Voltage 1.8 5.5 V
VCC2 Supply Voltage 2.5 5.5 V
VCC3 Supply Voltage 2.7 5.5 V
VCC4 Supply Voltage 4.5 5.5 V
ICC Supply Current VCC = 5.0V READ at 100 KHz 0.4 1.0 mA
ICC Supply Current VCC = 5.0V WRITE at 100 KHz 2.0 3.0 mA
ISB1 Standby Current VCC = 1.8V VIN = VCC or VSS 0.6 3.0 µA
ISB2 Standby Current VCC = 2.5V VIN = VCC or VSS 1.4 4.0 µA
ISB3 Standby Current VCC = 2.7V VIN = VCC or VSS 1.6 4.0 µA
ISB4 Standby Current VCC = 5.0V VIN = VCC or VSS 8.0 18.0 µA
ILI Input Leakage Current VIN = VCC or VSS 0.10 3.0 µA
ILO Output Leakage Current VOUT = VCC or VSS 0.05 3.0 µA
VIL Input Low Level(1) -0.6 VCC × 0.3 V
VIH Input High Level (1)
VCC × 0.7 VCC + 0.5 V
VOL2 Output Low Level VCC = 3.0V IOL = 2.1 mA 0.4 V
VOL1 Output Low Level VCC = 1.8V IOL = 0.15 mA 0.2 V
Note: 1. VIL min and VIH max are reference only and are not tested.

3
AC Characteristics
Applicable over recommended operating range from TA = -40°C to +85°C, VCC = +1.8V to +5.5V, CL = 1 TTL Gate and
100 pF (unless otherwise noted).
2.7-, 2.5-, 1.8-volt 5.0-volt
Symbol Parameter Min Max Min Max Units
fSCL Clock Frequency, SCL 100 400 KHz
tLOW Clock Pulse Width Low 4.7 1.2 µs
tHIGH Clock Pulse Width High 4.0 0.6 µs
(1)
tI Noise Suppression Time 100 50 ns
tAA Clock Low to Data Out Valid 0.1 4.5 0.1 0.9 µs
tBUF Time the bus must be free before a new 4.7 1.2 µs
transmission can start(1)
tHD.STA Start Hold Time 4.0 0.6 µs
tSU.STA Start Set-up Time 4.7 0.6 µs
tHD.DAT Data In Hold Time 0 0 µs
tSU.DAT Data In Set-up Time 200 100 ns
tR Inputs Rise Time(1) 1.0 0.3 µs
tF Inputs Fall Time(1) 300 300 ns
tSU.STO Stop Set-up Time 4.7 0.6 µs
tDH Data Out Hold Time 100 50 ns
tWR Write Cycle Time 10 10 ms
Write
Endurance(1) 5.0V, 25°C, Page Mode 1M 1M
Cycles
Note: 1. This parameter is characterized and is not 100% tested.

Device Operation
CLOCK and DATA TRANSITIONS: The SDA pin is nor- municating with the EEPROM) must pull the SDA bus low
mally pulled high with an external device. Data on the SDA to acknowledge that it has successfully received each
pin may change only during SCL low time periods (refer to word. This must happen during the ninth clock cycle after
Data Validity timing diagram). Data changes during SCL each word received and after all other system devices have
high periods will indicate a start or stop condition as freed the SDA bus. The EEPROM will likewise acknowl-
defined below. edge by pulling SDA low after receiving each address or
START CONDITION: A high-to-low transition of SDA with data word (refer to Acknowledge Response from Receiver
SCL high is a start condition which must precede any other timing diagram).
command (refer to Start and Stop Definition timing dia- STANDBY MODE: The AT24C01 features a low power
gram). standby mode which is enabled: (a) upon power-up and (b)
STOP CONDITION: A low-to-high transition of SDA with after the receipt of the STOP bit and the completion of any
SCL high is a stop condition which terminates all communi- internal operations.
cations. After a read sequence, the stop command will MEMORY RESET: After an interruption in protocol, power
place the EEPROM in a standby power mode (refer to Start loss or system reset, any 2-wire part can be reset by follow-
and Stop Definition timing diagram). ing these steps:
ACKNOWLEDGE: All addresses and data words are seri- (a) Clock up to 9 cycles, (b) look for SDA high in each cycle
ally transmitted to and from the EEPROM in 8-bit words. while SCL is high and then (c) create a start condition as
Any device on the system bus receiving data (when com- SDA is high.

4 AT24C01
 AT24C01

Bus Timing
SCL: Serial Clock, SDA: Serial Data I/O

Write Cycle Timing

SCL: Serial Clock, SDA: Serial Data I/O

SCL

SDA 8th BIT ACK

WORD n (1)
tWR

STOP START
CONDITION CONDITION

Note: 1. The write cycle time tWR is the time from a valid stop condition of a write sequence to the end of the internal clear/write
cycle.

5
Data Validity

Start and Stop Definition

Output Acknowledge

6 AT24C01
 AT24C01

Write Operations Read Operations

BYTE WRITE: Following a start condition, a write operation Read operations are initiated the same way as write opera-
requires a 7-bit data word address and a low write bit. Upon tions with the exception that the read/write select bit in the
receipt of this address, the EEPROM will again respond device address word is set to one. There are two read
with a zero and then clock in the first 8-bit data word. Fol- operations: byte read and sequential read.
lowing receipt of the 8-bit data word, the EEPROM will out- BYTE READ: A byte read is initiated with a start condition
p ut a z e r o an d t h e a d dr e s s i n g d e v i c e, s uc h a s a followed by a 7-bit data word address and a high read bit.
microcontroller, must terminate the write sequence with a The AT24C01 will respond with an acknowledge and then
stop condition. At this time the EEPROM enters an inter- serially output 8 data bits. The microcontroller does not
nally-timed write cycle to the nonvolatile memory. All inputs respond with a zero but does generate a following stop
are disabled during this write cycle , tWR, and the EEPROM condition (refer to Figure 3).
will not respond until the write is complete (refer to Figure
SEQUENTIAL READ: Sequential reads are initiated the
1).
same as a byte read. After the microcontroller receives an
PAGE WRITE: The AT24C01 is capable of a 4-byte page 8-bit data word, it responds with an acknowledge. As long
write. as the EEPROM receives an acknowledge, it will continue
A page write is initiated the same as a byte write but the to increment the data word address and serially clock out
microcontroller does not send a stop condition after the first sequential data words. When the memory address limit is
data word is clocked in. Instead, after the EEPROM reached, the data word address will “roll over” and the
acknowledges receipt of the first data word, the microcon- sequential read will continue. The sequential read opera-
troller can transmit up to three more data words. The tion is terminated when the microcontroller does not
EEPROM will respond with a zero after each data word respond with an input zero but does generate a following
received. The microcontroller must terminate the page stop condition (refer to Figure 4).
write sequence with a stop condition (refer to Figure 2).
The data word address lower 2 bits are internally incre-
mented following the receipt of each data word. The higher
five data word address bits are not incremented, retaining
the memory page row location. When the word address,
internally generated, reaches the page boundary, the fol-
lowing byte is placed at the beginning of the same page. If
more than four data words are transmitted to the EEPROM,
the data word address will “roll over” and previous data will
be overwritten.
ACKNOWLEDGE POLLING: Once the internally-timed
write cycle has started and the EEPROM inputs are dis-
abled, acknowledge polling can be initiated. This involves
sending a start condition followed by the device address
word. The read/write bit is representative of the operation
desired. Only if the internal write cycle has completed will
the EEPROM respond with a zero allowing the read or
write sequence to continue.
Figure 1. Byte Write

7
Figure 2. Page Write

Figure 3. Byte Read

Figure 4. Sequential Read

8 AT24C01
 AT24C01

Ordering Information
tWR (max) ICC (max) ISB (max) fMAX
(ms) (µA) (µA) (kHz) Ordering Code Package Operation Range
10 3000 18 400 AT24C01-10PC 8P3 Commercial
AT24C01-10SC 8S1 (0°C to 70°C)
AT24C01-10MC 8M
AT24C01-10TC 8T
3000 18 400 AT24C01-10PI 8P3 Industrial
AT24C01-10SI 8S1 (-40°C to 85°C)
AT24C01-10MI 8M
AT24C01-10TI 8T
10 1500 4 100 AT24C01-10PC-2.7 8P3 Commercial
AT24C01-10SC-2.7 8S1 (0°C to 70°C)
AT24C01-10MC-2.7 8M
AT24C01-10TC-2.7 8T
1500 4 100 AT24C01-10PI-2.7 8P3 Industrial
AT24C01-10SI-2.7 8S1 (-40°C to 85°C)
AT24C01-10MI-2.7 8M
AT24C01-10TI-2.7 8T
10 1000 4 100 AT24C01-10PC-2.5 8P3 Commercial
AT24C01-10SC-2.5 8S1 (0°C to 70°C)
AT24C01-10MC-2.5 8M
AT24C01-10TC-2.5 8T
1000 4 100 AT24C01-10PI-2.5 8P3 Industrial
AT24C01-10SI-2.5 8S1 (-40°C to 85°C)
AT24C01-10MI-2.5 8M
AT24C01-10TI-2.5 8T
10 800 3 100 AT24C01-10PC-1.8 8P3 Commercial
AT24C01-10SC-1.8 8S1 (0°C to 70°C)
AT24C01-10MC-1.8 8M
AT24C01-10TC-1.8 8T
800 3 100 AT24C01-10PI-1.8 8P3 Industrial
AT24C01-10SI-1.8 8S1 (-40°C to 85°C)
AT24C01-10MI-1.8 8M
AT24C01-10TI-1.8 8T

Package Type
8M 8-Lead, 0.118” Wide, Miniature Small Outline Package (MSOP)
8P3 8-Lead, 0.300" Wide, Plastic Dual Inline Package (PDIP)
8S1 8-Lead, 0.150" Wide, Plastic Gull Wing Small Outline (JEDEC SOIC)
8T 8-Lead, 0.170” Wide, Thin Shrink Small Outline Package (TSSOP)
Options
Blank Standard Operation (4.5V to 5.5V)
-2.7 Low-Voltage (2.7V to 5.5V)
-2.5 Low-Voltage (2.5V to 5.5V)
-1.8 Low-Voltage (1.8V to 5.5V)

9
Packaging Information
8M, 8-Lead, 0.118” Wide, Miniature Small Outline 8P3, 8-Lead, 0.300” Wide, Plastic Dual Inline
Package (MSOP) Package (PDIP)
Dimensions in Inches and (Millimeters)
JEDEC STANDARD MS-001 BA

.400 (10.16)
0.40 (0.016)
.355 (9.02)
0.25 (0.010)
PIN
1
3.10 (0.122)
2.90 (0.114) .280 (7.11)
PIN 1 .240 (6.10)

.037 (.940)
0.65 (0.026) TYP .027 (.690)
.300 (7.62) REF

3.10 (0.122) .210 (5.33) MAX .100 (2.54) BSC

2.90 (0.114)
1.10 (0.043) SEATING
0.97 (0.038) PLANE

.015 (.380) MIN

.150 (3.81)
0.15 (0.006) .115 (2.92) .022 (.559)
0.05 (0.002) .014 (.356)
.070 (1.78)
.045 (1.14)
0.23 (0.009)
0.13 (0.005) .325 (8.26)
.300 (7.62)
3.81
(0.150) 0
REF
REF .012 (.305) 15
4.90 (0.193) .008 (.203)
REF .430 (10.9) MAX

8S1, 8-Lead, 0.150” Wide, Plastic Gull Wing Small 8T, 8-Lead 0.170” Wide, Thin Shrink Small Outline
Outline (JEDEC SOIC) Package (TSSOP)
Dimensions in Inches and (Millimeters) Dimensions in Millimeters and (Inches)*

PIN 1
.020 (.508)
.013 (.330)
6.50 (.256)
6.25 (.246)
.157 (3.99) .244 (6.20)
.150 (3.81) .228 (5.79)
PIN 1

0.30 (.012)
.050 (1.27) BSC 0.19 (.008)

3.10 (.122)
.196 (4.98) 2.90 (.114)
1.05 (.041) 1.20 (.047) MAX
.189 (4.80) 0.80 (.033)
.068 (1.73)
.053 (1.35)
.65 (.026) BSC 0.15 (.006)
0.05 (.002)
.010 (.254)
.004 (.102) 4.5 (.177)
4.3 (.169)
0.20 (.008)
0
REF .010 (.254) 0.09 (.004)
8
.007 (.203)
0.75 (.030)
0 REF 0.45 (.018)
.050 (1.27) 8
.016 (.406)
*Controlling dimension: millimeters

10 AT24C01