AT24LC512
Features
Low-voltage Operation
Compatibility
1.8 (VCC = 1.8V to 5.5V)
Write Protect Pin for Hardware Data Protection
Operating Ambient Temperature: -40°C to
128-byte Page (512K) Write Modes
Partial Page Writes Allowed
+85°C
Internally Organized 65,536 X 8 (512K),
Self-timed Write Cycle (5 ms max)
Two-wire Serial Interface
High-reliability
Schmitt Trigger, Filtered Inputs for Noise
Endurance: 1 Million Write Cycles
Data Retention: 100 Years
8-lead DIP, 8-lead JEDEC SOP,8-lead MSOP
Suppression
Bidirectional Data Transfer Protocol
1MHZ(5V),400 kHz (1.8V, 2.5V, 2.7V)
and 8-lead TSSOP Packages
General Description
The AT24LC512 provides 524,288 bits of serial electrically erasable and programmable read only memory
(EEPROM) organized as 65,536 words of 8 bits each. The device’s cascadable feature allows up to eight
devices to share a common two-wire bus.
The device is optimized for use in many industrial and commercial applications where low-power and
low-voltage operation are essential. The devices are available in space-saving 8-pin PDIP, 8-lead JEDEC SOP,
8-lead EIAJ SOP, 8-lead TSSOP.
Ordering Information
DEVICE
Package Type
MARKING
Packing
Packing Qty
AT24LC512N
DIP-8L
24LC512
TUBE
2000pcs/box
AT24LC512M/TR
SOP-8L
24LC512
REEL
2500pcs/reel
AT24LC512MM/TR
MSOP-8L
LC512
REEL
3000pcs/reel
AT24LC512MT/TR
TSSOP-8L
LC512
REEL
3000pcs/reel
Pin Configuration
8-lead DIP
http://www.hgsemi.com.cn
8-lead TSSOP
1 / 14
8-lead SOP/MSOP
2022 JUNE
AT24LC512
Pin Descriptions
Table 1:Pin Configuration
Pin Designation
Type
Name and Functions
A0-A2
I
Address Inputs
SAD
I/O & Open-drain
Serial Data
SCL
I
Serial Clock Input
WP
I
Write Protect
GND
P
Ground
VCC
P
Power Supply
NC
NC
No Connect
Block Diagram
http://www.hgsemi.com.cn
2 / 14
2022 JUNE
AT24LC512
Pin Descriptions
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 opendraindriven 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 are hardwired (directly to GND or to Vcc) for compatibility with other HX24LC512B devices.
When the pins are hardwired, as many as eight 512K devices may be addressed on a single bus system.
(Device addressing is discussed in detail under “Device Addressing,” page 8.) A device is selected when a
corresponding hardware and software match is true. If these pins are left floating, the A2, A1, and A0 pins will
be internally pulled down to GND. However, due to capacitive coupling that may appear during customer
applications, Fs-Rank recommends always connecting the address pins to a known state. When using a
pull-up resistor, Fs-Rank recommendsusing 10kΩ or less.
WRITE PROTECT (WP): The write protect input, when connected to GND, allows normal write operations.
When WP is connected directly to Vcc, all write operations to the memory are inhibited.If the pin is left floating,
the WP pin will be internally pulled down to GND. However, due to capacitive coupling that may appear during
customer applications, Fs-Rank recommends always connecting the WP pins to a known state. When using a
pull-up resistor, Fs-Rank recommends using 10kΩ or less.
Table 2: Write Protect
Part of the Array Protected
WP Pin Status:
AT24LC512
At VCC
Full (512K) Array
At GND
Normal Read/Write Operations
Memory Organization
AT24LC512, 512 SERIAL EEPROM: The 512K is internally organized as 512 pages of 128 bytes each.
Random word addressing requires a 16-bit data word address.
Device Operation
CLOCK and DATA TRANSITIONS: The SDA pin is normally pulled high with an external device. Data on the
SDA pin may change only during SCL low time periods (see to Figure 1 on page 4). Data changes duringSCL
high periods will indicate a start or stop condition as defined below.
START CONDITION: A high-to-low transition of SDA with SCL high is a start condition which must precedeany
other command (see to Figure 2 on page 5).
STOP CONDITION: A low-to-high transition of SDA with SCL high is a stop condition. After a read sequence,the
stop command will place the EEPROM in a standby power mode (see Figure 2 on page 5).
ACKNOWLEDGE: All addresses and data words are serially transmitted to and from the EEPROM in 8-bit
words. The EEPROM sends a “0” to acknowledge that it has received each word. This happens during the
ninth clock cycle
STANDBY MODE: The AT24LC512 features a low-power standby mode which is enabled: (a) upon power-up
http://www.hgsemi.com.cn
3 / 14
2022 JUNE
AT24LC512
and (b) after the receipt of the STOP bit and the completion of any internal operations
MEMORY RESET: After an interruption in protocol, power loss or system reset, any two-wire part can bereset
by following these steps:
1. Clock up to 9 cycles.
2. Look for SDA high in each cycle while SCL is high.
3.
Create a start condition.
Figure 1.
Data Validity
Figure 2. Start and Stop Definition
Figure 3. Output Acknowledge
http://www.hgsemi.com.cn
4 / 14
2022 JUNE
AT24LC512
Device Addressing
The 512K EEPROM devices all require an 8-bit device address word following a start condition to enable the
chip for a read or write operation (see to Figure 4 on page 4).
The device address word consists of a mandatory “1”, “0” sequence for the first four most significant bits as
shown. This is common to all the Serial EEPROM devices.
The 512K uses the three device address bits A2,A1, A0 to allow as many as eight devices on the same bus.
These bits must compare to their corresponding hardwired input pins. The A2,A1 and A0 pins use an internal
proprietary circuit that biases them to a logic low condition if the pins are allowed to float.
The eighth bit of the device address is the read/write operation select bit. A read operation is initiated if thisbit is
high and a write operation is initiated if this bit is low.
Upon a compare of the device address, the EEPROM will output a “0”. If a compare is not made, the chip will
return to a standby state.
DATA SECURITY: The AT24LC512 has a hardware data protection scheme that allows the user to writeprotect
the entire memory when the WP pin is at VCC.
Write Operations
BYTE WRITE: A write operation requires two 8-bit data word addresses following the device address word and
acknowledgment. Upon receipt of this address, the EEPROM will again respond with a “0” and then clock in the
first 8-bit data word. Following receipt of the 8-bit data word, the EEPROM will output a “0”. The addressing
device, such as a microcontroller, then must terminate the write sequence with a stop condition. At this time the
EEPROM enters an internally-timed write cycle, tWR, to the nonvolatile memory. All inputs are disabled during
this write cycle and the EEPROM will not respond until the write is complete (see Figure 6-2 on page10).
PAGE WRITE: The 512K EEPROM is capable of 128-byte page writes.
A page write is initiated the same way as a byte write, but the microcontroller does not send a stop condition
after the first data word is clocked in. Instead, after the EEPROM acknowledges receipt of the first data word,
the microcontroller can transmit up to 127 more data words. The EEPROM will respond with a “0” after each
data word received. The microcontroller must terminate the page write sequence with a stop condition (see
Figure 6-3 on page 11).
The data word address lower 7 bits are internally incremented following the receipt of each data word. The
higher data word address bits are not incremented, retaining the memory page row location. When the word
address, internally generated, reaches the page boundary, the followingbyte is placed at the beginning of the
same page. If more than 128 data words are
transmitted to the EEPROM, the data word address will “roll over” and previous data will be overwritten. The
address roll over during write is from the last byte of the current page to the firstbyte of the same page.
ACKNOWLEDGE POLLING: Once the internally-timed write cycle has started and the EEPROM inputs are
disabled, 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 “0”, allowing the read or
write sequence to continue.
http://www.hgsemi.com.cn
5 / 14
2022 JUNE
AT24LC512
Read Operations
Read operations are initiated the same way as write operations with the exception that the Read/Write select bit
in the device address word is set to “1”. There are three read operations:current address read, random address
read and sequential read.
CURRENT ADDRESS READ: The internal data word address counter maintains the last
address accessed during the last read or write operation, incremented by “1”. This address staysvalid between
operations as long as the chip power is maintained. The address roll over during read is from the last byte of the
last memory page, to the first byte of the first page.
Once the device address with the Read/Write select bit set to “1” is clocked in and acknowledged by the
EEPROM, the current address data word is serially clocked out. The
microcontroller does not respond with an input “0” but does generate a following stop condition(see Figure 6-4
on page 11).
RANDOM READ: A random read requires a “dummy” byte write sequence to load in the data word address.
Once the device address word and data word address are clocked in and acknowledged by the EEPROM, the
microcontroller must generate another start condition. Themicrocontroller now initiates a current address read
by sending a device address with the Read/Write select bit high. The EEPROM acknowledges the device
address and serially clocks
out the data word. The microcontroller does not respond with a “0” but does generate a followingstop condition
(see Figure 6-5 on page 11).
SEQUENTIAL READ: Sequential reads are initiated by either a current address read or a randomaddress read.
After the microcontroller receives a data word, it responds with an acknowledge. As long as the EEPROM
receives an acknowledge, it will continue to increment the data word address and serially clock out sequential
data words. When the memory addresslimit is reached, the data word address will roll over and the sequential
read will continue. The
sequential read operation is terminated when the microcontroller does not respond with a “0” butdoes generate
a following stop condition (see Figure 6-6 on page 11).
http://www.hgsemi.com.cn
6 / 14
2022 JUNE
AT24LC512
Figure 4. Device Address
Figure 5. Byte Write
Figure 6. Page Write
http://www.hgsemi.com.cn
7 / 14
2022 JUNE
AT24LC512
Figure 7. Current Address Read
Figure 8. Random Read
Figure 9. Sequential Read
http://www.hgsemi.com.cn
8 / 14
2022 JUNE
AT24LC512
Electrical Characteristics
Absolute Maximum Stress Ratings
DC Supply Voltage...............................................................................V to +6.5V
Input / Output Voltage....................................................GND-0.3V to VCC+0.3V
Operating Ambient Temperature......................................................-40°C to +85°C
Storage Temperature................................................................... -65°C to +150°C
*Comments
Stresses above those listed under "Absolute Maximum
Ratings" may cause permanent damage to this
device. These are stress ratings only. Functional operation of this device at these or any other conditions above
those indicated in the operational sections of this specification is not implied or intended. Exposure to the
absolute maximum rating conditions for extended periods may affect device reliability.
DC Electrical Characteristics
Applicable over recommended operating range from: TA = –40°C to +85°C, VCC = +1.7V to +5.5V (unless
otherwise noted)
Parameter
Symbol
Min.
Typ.
Max.
Unit
Supply Voltage
VCC1
1.8
-
5.5
V
Supply Voltage
VCC2
2.5
-
5.5
V
Supply Voltage
VCC3
2.7
-
5.5
V
Supply Voltage
VCC4
4.5
-
5.5
V
Supply Current VCC = 5.0V
ICC1
-
0.4
1.0
mA
READ at 400 kHz
Supply Current VCC = 5.0V
ICC2
-
2.0
3.0
mA
WRITE at 400 kHz
Standby Current VCC = 1.7V
ISB1
-
0.6
1.0
µA
VIN = VCC or VSS
Standby Current VCC = 2.5V
ISB2
-
1.0
2.0
µA
VIN = VCC or VSS
Standby Current VCC = 2.7V
ISB3
-
1.0
2.0
µA
VIN = VCC or VSS
Standby Current VCC = 5.0V
ISB4
-
1.0
5.0
µA
VIN = VCC or VSS
Input Leakage Current
ILI
-
0.10
3.0
µA
VIN = VCC or VSS
Output Leakage Current
ILO
-
0.05
3.0
µA
VOUT = VCC or VSS
Input Low Level
VIL
–0.3
--
Input High Level
VIH
VCC x0.7
-
Output Low Level VCC =5.0V
VOL3
-
-
0.4
V
IOL = 3.0 mA
Output Low Level VCC =3.0V
VOL2
-
-
0.4
V
IOL = 2.1 mA
Output Low Level VCC =1.7V
VOL1
-
-
0.2
V
IOL = 0.15 mA
http://www.hgsemi.com.cn
9 / 14
VCC x
0.3
VCC +
0.3
Condition
V
V
2022 JUNE
AT24LC512
Pin Capacitance
Applicable over recommended operating range from TA = 25°C, f = 1.0 MHz, VCC = +1.7V
Parameter
Input/Output
Capacitance
(SDA)
Input Capacitance
(A0, A1,A2,SCL)
Symbol
Min.
Typ.
Max.
Unit
Condition
CI/O
-
-
8
pF
VI/O = 0V
CIN
-
-
6
pF
VIN = 0V
AC Electrical Characteristics
Applicable over recommended operating range from TA = –40°C to +85°C, VCC = +1.7V to +5.5V, CL = 1 TTL
Gate and 100 pF (unless otherwise noted)
Parameter
Symbol
1.7-volt
5.0-volt
Min.
Typ.
Max.
Min.
Typ.
Max.
Units
Clock Frequency, SCL
fSCL
-
-
400
-
-
1000
kHz
Clock Pulse Width Low
tLOW
1.2
-
-
0.6
-
-
µs
Clock Pulse Width High
tHIGH
0.6
-
-
0.4
-
-
µs
Noise Suppression Time
tI
-
-
50
-
-
50
ns
Clock Low to Data Out Valid
tAA
0.1
-
0.9
0.09
-
0.9
µs
Time the bus must be free
before a new transmission
can start
tBUF
1.2
-
-
0.5
-
-
µs
Start Hold Time
tHD.STA
0.6
-
-
0.25
-
-
µs
Start Setup Time
tSU.STA
0.6
-
-
0.25
-
-
µs
Data In Hold Time
tHD.DAT
0
0
-
0
-
0
µs
Data In Setup Time
tSU.DAT
100
0
-
100
-
0
ns
Inputs Rise Time
tR
-
-
0.3
-
-
0.3
µs
Inputs Fall Time
tF
-
-
300
-
-
300
ns
Stop Setup Time
tSU.STO
0.6
-
-
0.25
-
-
µs
Data Out Hold Time
tDH
50
-
-
50
-
-
ns
Write Cycle Time
tWR
-
5
5
-
-
5
ms
Endurance
1M
-
-
-
-
WriteCycles
5.0V, 25°C, Byte Mode
http://www.hgsemi.com.cn
10 / 14
2022 JUNE
AT24LC512
Bus Timing
Figure 10. SCL: Serial Clock, SDA: Serial Data I/O
Write Cycle Timing
Figure 11. SCL: Serial Clock, SDA: Serial Data I/O
http://www.hgsemi.com.cn
11 / 14
2022 JUNE
AT24LC512
PHYSICAL DIMENSIONS
SOP-8L
Q
A
C
C1
B
D
A1
a
0.25
b
Dimensions In Millimeters(SOP8L)
A
A1
B
C
C1
D
Min:
1.35
0.05
4.90
5.80
3.80
0.40
0°
0.35
Max:
1.55
0.20
5.10
6.20
4.00
0.80
8°
0.45
Symbol:
Q
a
b
1.27 BSC
DIP-8L
D1
L1
L
E
B
d
D
A
c
a
b
Dimensions In Millimeters(DIP8L)
A
B
D
D1
E
L
L1
a
b
c
Min:
6.10
9.00
8.40
7.42
3.10
0.50
3.00
1.50
0.85
0.40
Max:
6.68
9.50
9.00
7.82
3.55
0.70
3.60
1.55
0.90
0.50
Symbol:
http://www.hgsemi.com.cn
12 / 14
d
2.54 BSC
2022 JUNE
AT24LC512
Physical Dimensions
MSOP8
Q
A
C1
C
B
A1
D
0.20
b
a
Dimensions In Millimeters(MSOP8L)
A
A1
B
C
C1
D
Min:
0.80
0.05
2.90
4.75
2.90
0.35
0°
0.25
Max:
0.90
0.20
3.10
5.05
3.10
0.75
8°
0.35
Symbol:
Q
a
b
0.65 BSC
TSSOP8
Q
A
A1
D
C1
C
B
a
b
0.25
Dimensions In Millimeters(TSSOP8L)
A
A1
B
C
C1
D
Min:
0.750
0
2.900
3.900
2.900
0.330
0°
Max:
0.950
0.150
3.100
4.100
3.100
0.470
8°
Symbol:
http://www.hgsemi.com.cn
13 / 14
Q
a
b
0.300TYP
0.650 TYP
2022 JUNE
AT24LC512
IMPORTANT STATEMENT:
Huaguan Semiconductor Co,Ltd. reserves the right to change the products and
services provided without notice. Customers should obtain the latest relevant
information before ordering, and verify the timeliness and accuracy of this
information.
Customers are responsible for complying with safety standards and taking safety
measures when using our products for system design and machine manufacturing to
avoid potential risks that may result in personal injury or property damage.
Our products are not licensed for applications in life support, military, aerospace,
etc., so we do not bear the onsequences of the application of these products in these
fields.
Huaguan Semiconductor Co,Ltd. the performance of the semiconductor products
produced by the company can reach the performance indicators that can be applied
at the time of sales. The use of testing and other quality control technologies is limite
d to the quality assurance scope of Huaguan semiconductor. Not all parameters of
each device need to be tested. The above documents are for reference only, and all
are subject to the physical parameters.
Our documentation is only permitted to be copied without any tampering with the
content, so we do not accept any responsibility or liability for the altered documents.
http://www.hgsemi.com.cn
14 / 14
2022 JUNE