– Endurance: 100,000 Write Cycles
– Data Retention: 40 Years
– ESD Protection: >4000V
• Automotive Grade and Extended Temperature Devices Available
• 8-pin PDIP and 20-pin JEDEC SOIC, 8-pin LAP, and 8-ball dBGA
TM
Packages
Description
The AT24C512 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 4 devices to share a common 2-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, 20-pin JEDEC SOIC, 8-pin Leadless Array (LAP), and 8-ball dBGA
ages. In addition, the entire family is available in 5.0V (4.5V to 5.5V), 2.7V (2.7V to
5.5V) and 1.8V (1.8V to 3.6V) versions.
pack-
2-wire Serial
EEPROM
512K (65,536 x 8)
AT24C512
Pin Configurations
Pin NameFunction
A0 - A1Address Inputs
SDASerial Data
SCLSerial Clock Input
WPWrite Protect
NCNo Connect
20-pin SOIC
8-pin PDIP
A0
A1
NC
GND
1
2
3
4
8
7
6
5
8-pin Leadless Array
VCC
WP
SCL
SDA
8
7
6
5
A0
1
A1
2
NC
3
GND
4
Bottom View
8-ball dBGA
VCC
WP
SCL
SDA
8
7
6
5
A0
2
A1
3
NC
4
GND
1
Bottom View
VCC
WP
SCL
SDA
Rev. 1116D–07/00
1
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
*NOTICE:Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent damage 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.
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 (A1, A0): The A1 and A0
pins are device address inputs that are hardwired or left not
connected for hardware compatibility with AT24C128/256.
When the pins are hardwired, as many as four 512K
devices may be addressed on a single bus system (device
addressing is discussed in detail under the Device
Addressing section). When the pins are not hardwired, the
default A1 and A0 are zero.
2
AT24C512
WRITE PROTECT (WP): The write protect input, when tied
to GND, allows normal write operations. When WP is tied
high to V
ited. If left unconnected, WP is internally pulled down to
GND. Switching WP to V
ates a software write protect function.
, all write operations to the memory are inhib-
CC
prior to a write operation cre-
CC
Memory Organization
AT24C512, 512K SERIAL EEPROM: The 512K is inter-
nally organized as 512 pages of 128-bytes each. Random
word addressing requires a 16-bit data word address.
AT24C512
Pin Capacitance
(1)
Applicable over recommended operating range from TA = 25°C, f = 1.0 MHz, VCC = +1.8V.
SymbolTest ConditionMaxUnitsConditions
C
I/O
C
IN
Input/Output Capacitance (SDA)8pFV
I/O
= 0V
Input Capacitance (A0, A1, SCL)6pFVIN = 0V
Note:1. This parameter is characterized and is not 100% tested.
DC Characteristics
Applicable over recommended operating range from: T
= +1.8V to +5.5V (unless otherwise noted).
V
CC
SymbolParameterTest ConditionMinTypMaxUnits
V
V
V
I
I
I
CC1
CC2
CC3
CC1
CC2
SB1
Supply Voltage1.83.6V
Supply Voltage2.75.5V
Supply Voltage4.55.5V
Supply CurrentVCC = 5.0VREAD at 400 kHz1.02.0mA
Supply CurrentVCC = 5.0VWRITE at 400 kHz2.03.0mA
V
= 1.8V
Standby Current
(1.8V option)
CC
VCC = 3.6V2.0
= -40°C to +85°C, VCC = +1.8V to +5.5V, TAC = 0°C to +70°C,
AI
0.2µA
= VCC or V
V
IN
SS
I
SB2
I
SB3
I
LI
I
LO
V
IL
V
IH
V
OL2
V
OL1
Note:1.V
= 2.7V
V
Standby Current
(2.7V option)
Standby Current
(5.0V option)
CC
V
= 5.5V6.0
CC
= 4.5 - 5.5VVIN = VCC or V
V
CC
Input Leakage CurrentVIN = V
Output Leakage
Current
Input Low Level
Input High Level
(1)
(1)
V
= V
OUT
CC or VSS
CC or VSS
= VCC or V
V
IN
SS
SS
0.103.0µA
0.053.0µA
-0.6VCC x 0.3V
VCC x 0.7VCC + 0.5V
0.6µA
6.0µA
Output Low LevelVCC = 3.0VIOL = 2.1 mA0.4V
Output Low LevelVCC = 1.8VIOL = 0.15 mA0.2V
min and VIH max are reference only and are not tested.
IL
3
AC Characteristics
Applicable over recommended operating range from TA = -40°C to +85°C, VCC = +1.8V to +5.5V, CL = 100 pF (unless otherwise noted). Test conditions are listed in Note 2.
1.8-volt 2.7-volt5.0-volt
SymbolParameter
f
SCL
t
LOW
t
HIGH
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
Clock Frequency, SCL1004001000kHz
Clock Pulse Width Low4.71.30.6µs
Clock Pulse Width High4.01.00.4µs
Clock Low to Data Out Valid0.14.50.050.90.050.55µs
Time the bus must be free before a new
transmission can start
(1)
Start Hold Time4.00.60.25µs
Start Set-up Time4.70.60.25µs
Data In Hold Time000µs
Data In Set-up Time200100100ns
Inputs Rise Time
Inputs Fall Time
(1)
(1)
Stop Set-up Time4.70.60.25µs
Data Out Hold Time1005050ns
Write Cycle Time201010ms
(1)
5.0V, 25°C, Page Mode100K100K100KWrite Cycles
Notes: 1. This parameter is characterized and is not 100% tested.
2. AC measurement conditions:
R
(connects to VCC): 1.3KΩ (2.7V, 5V), 10KΩ (1.8V)
L
Input pulse voltages: 0.3V
to 0.7V
CC
CC
Input rise and fall times: ≤50ns
Input and output timing reference voltages: 0.5V
CC
UnitsMinMaxMinMaxMinMax
4.71.30.5µs
1.00.30.3µs
300300100ns
Device Operation
CLOCK and DATA TRANSITIONS: The SDA pin is nor-
mally pulled high with an external device. Data on the SDA
pin may change only during SCL low time periods (refer to
Data Validity timing diagram). Data changes during SCL
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 precede any other
command (refer to Start and Stop Definition timing diagram).
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 (refer to Start and Stop Definition timing diagram).
4
AT24C512
ACKNOWLEDGE: All addresses and data words are seri-
ally transmitted to and from the EEPROM in 8-bit words.
The EEPROM sends a zero during the ninth clock cycle to
acknowledge that it has received each word.
STANDBY MODE: The AT24C512 features a low power
standby mode which is enabled: a) upon power-up 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 2-wire part can be reset by following these steps:
(a) Clock up to 9 cycles, (b) look for SDA high in each cycle
while SCL is high and then (c) create a start condition as
SDA is high.
AT24C512
Bus Timing (SCL: Serial Clock, SDA: Serial Data I/O)
Write Cycle Timing (SCL: Serial Clock, SDA: Serial Data I/O)
(1)
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
AT24C512
AT24C512
Device Addressing
The 512K EEPROM requires an 8-bit device address word
following a start condition to enable the chip for a read or
write operation (refer to Figure 1). The device address word
consists of a mandatory one, zero sequence for the first
five most significant bits as shown. This is common to all 2wire EEPROM devices.
The 512K uses the two device address bits A1, A0 to allow
as many as four devices on the same bus. These bits must
compare to their corresponding hardwired input pins. The
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 this bit 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 zero. If a compare is not made, the device will
return to a standby state.
DATA SECURITY: The AT24C512 has a hardware data
protection scheme that allows the user to write protect the
whole memory when the WP pin is at V
CC
.
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 zero and then clock in
the first 8-bit data word. Following receipt of the 8-bit data
word, the EEPROM will output a zero. 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, t
nonvolatile memory. All inputs are disabled during this write
cycle and the EEPROM will not respond until the write is
complete (refer to Figure 2).
PAG E WR I TE: 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 zero after each data word
received. The microcontroller must terminate the page
write sequence with a stop condition (refer to Figure 3).
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 following
byte is placed at the beginning of the same page. If more
than 128 data words are transmitted to the EEPROM, the
, to the
WR
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 first byte 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 zero, allowing the read or
write sequence to continue.
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 one. 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 one.
This address stays valid 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 one 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 zero but
does generate a following stop condition (refer to Figure 4).
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. The microcontroller
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
zero but does generate a following stop condition (refer to
Figure 5).
SEQUENTIAL READ: Sequential reads are initiated by
either a current address read or a random address 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 address limit 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 zero but does
generate a following stop condition (refer to Figure 6).
Atmel Corporation makes no warranty for the use of its products, other than those expressly contained in the Company’s standard warranty which is detailed in Atmel’s Terms and Conditions located on the Company’s web site. The Company assumes no responsibility for
any errors which may appear in this document, reserves the right to change devices or specifications detailed herein at any time without
notice, and does not make any commitment to update the information contained herein. No licenses to patents or other intellectual property of Atmel are granted by the Company in connection with the sale of Atmel products, expressly or by implication. Atmel’s products are
not authorized for use as critical components in life support devices or systems.
Marks bearing ® and/or ™ are registered trademarks and trademarks of Atmel Corporation.
Terms and product names in this document may be trademarks of others.
Printed on recycled paper.
1116D–07/00/xM
Loading...
+ hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.