Document Outline
- SA24C512 Datasheet
- Features
- General Description
- Table of Contents
- List of Figures
- List of Tables
- Block Diagram
- Connection Diagram
- Ordering Information
- Product Specifications
- Absolute Maximum Ratings Operating Conditions
- ESD/Latchup Specification (JEDEC 8 Spec)
- Operating Conditions
- DC Electrical Characteristics (VCC 2.7V to 3.6V)
- Capacitance
- AC Test Conditions
- AC Testing Input/Output Waveforms
- AC Characteristics (VCC 2.7V to 3.6V)
- Bus Timing
- Write Cycle Timing
- Typical System Configuration
- Background Information (IIC Bus)
- Slave Address
- Device Type
- Device/Page Block Selection
- Read/Write Bit
- Acknowledge
- Array Address#1
- Array Address#0
- Pin Descriptions
- Serial Clock (SCL)
- Serial Data (SDA)
- Write Protect (WP)
- Device Selection Inputs A1 and A0 (as Appropriate)
- Device Operation
- Clock and Data Conventions
- START Condition
- STOP Condition
- SA24C512 Array Addressing
- Switching from F/S to HS Mode and Back
- Write Operations
- Byte Write
- Page Write
- Acknowledge Polling Write Protection
- Read Operations
- Current Address Read
- Random Read
- Sequential Read
- Physical Dimensions
- Contact Information
- Life Support Policy
This Datasheet states Saifun's current technical specifications regarding the Products described herein. This Datasheet
may be revised by subsequent versions or modifications due to changes in technical specifications.
Publication# 1907 Rev: 1 Amendment: 1
Issue Date: 10 September 2003
SA24C512
Datasheet
Features
=
Saifun NROMTM NVM Technology
=
Operating voltage: 2.7V to 3.6V
=
Clock frequency: 100/400/1700/3400 kHz
=
Low power consumption
0.5
A standby current typical (L version)
<0.2
A standby current typical (LZ version)
=
Write Modes
Byte Mode
Page Mode (128 Bytes/Page)
=
Schmitt trigger inputs
=
Hardware and software write protection for entire or partial array
=
Endurance: up to 1 million data changes
=
Data Retention: Greater than 40 years
=
Packages: 8-Pin DIP, 8-Pin SOIC and MLF Leadless
=
Temperature range
Commercial: 0C to +70C
Industrial (E): -40C to +85C
512Kb EEPROM IIC
http://www.saifun.com
Saifun NROM
TM
is a trademark of Saifun Semiconductors Ltd.
SA24C512 Datasheet
SAIFUN
2
General Description
SA24C512 is a 512-Kbit CMOS non-
volatile serial EEPROM organized as 64K x
8 bit memory. This device conforms to
Extended IIC 2-wire protocol that allows
accessing of memory in excess of 16Kbit
on an IIC bus. This serial communication
protocol uses a Clock signal (SCL) and a
Data signal (SDA) to synchronously clock
data between a master (e.g. a
microcontroller) and a slave (EEPROM).
SA24C512 offers hardware write protection
whereby the entire memory array can be
write protected by pulling WP pin to logic
HIGH. The entire memory then becomes
unalterable until the WP pin is switched to
logic LOW. The device also features
programmable write protect with options of
full, half, or a quadrant of the array.
The "LZ" version of the SA24C512 offers
very low standby current, making it suitable
for low-power applications. SA24C512 is
designed to minimize pin count and
simplify PC board layout requirements.
This device is offered in SO, DIP and
Leadless MLF packages.
Saifun's EEPROMs are designed and
tested for applications requiring high
endurance, high reliability and low power
consumption.
SA24C512 Datasheet
SAIFUN
3
Table of Contents
Features ......................................................................... 1
General Description ...................................................... 2
Block Diagram ............................................................... 4
Connection Diagram ..................................................... 5
Ordering Information .................................................... 6
Product Specifications ................................................. 7
Absolute Maximum Ratings Operating Conditions... 7
ESD/Latchup Specification (JEDEC 8 Spec) ........... 7
Operating Conditions............................................... 7
DC Electrical Characteristics (VCC 2.7V to 3.6V).... 8
Capacitance ............................................................ 8
AC Test Conditions ................................................. 9
AC Testing Input/Output Waveforms....................... 9
AC Characteristics (V
CC
2.7V to 3.6V)..................... 9
Bus Timing ............................................................ 10
Write Cycle Timing ................................................ 11
Typical System Configuration................................ 11
Background Information (IIC Bus) ............................. 12
Slave Address ....................................................... 12
Device Type .......................................................... 13
Device/Page Block Selection................................. 13
Read/Write Bit....................................................... 13
Acknowledge......................................................... 13
Array Address#1.................................................... 13
Array Address#0.................................................... 13
Pin Descriptions.......................................................... 14
Serial Clock (SCL)................................................. 14
Serial Data (SDA).................................................. 14
Write Protect (WP) ................................................ 14
Choice 1: Full Array Write Protect ................. 14
Choice 2: Programmable Write Protect ......... 15
Device Selection Inputs A1 and A0
(as Appropriate)..................................................... 16
Device Operation......................................................... 17
Clock and Data Conventions ................................. 17
START Condition .................................................. 17
STOP Condition .................................................... 17
SA24C512 Array Addressing................................. 17
Switching from F/S to HS Mode and Back............. 18
Write Operations ......................................................... 21
Byte Write ............................................................. 21
Page Write ............................................................ 21
Acknowledge Polling ............................................. 22
Write Protection .................................................... 22
Read Operations.......................................................... 23
Current Address Read........................................... 23
Random Read ....................................................... 23
Sequential Read.................................................... 23
Physical Dimensions................................................... 25
Contact Information .................................................... 28
Life Support Policy...................................................... 28
List of Figures
Figure 1. SA24C512 Block Diagram................................ 4
Figure 2. SO, Package (MW), Dual-in-Line Package (N),
Top View ............................................................... 5
Figure 3. Leadless Package (MLF), Top View ................. 5
Figure 4. SA24C512 Ordering Information ...................... 6
Figure 5. AC Testing Input/Output Waveforms ................ 9
Figure 6. Bus Timing ..................................................... 10
Figure 7. Write Cycle Timing ......................................... 11
Figure 8. Typical System Configuration......................... 11
Figure 9 Slave Address ................................................. 12
Figure 10. Data Transfer in Hs-mode ............................ 18
Figure 11. A Complete Hs-mode Transfer ..................... 19
Figure 12. Data Validity ................................................. 19
Figure 13. START and STOP Definition ........................ 20
Figure 14. Acknowledge Response from Receiver ........ 20
Figure 15. Byte Write .................................................... 22
Figure 16. Page Write ................................................... 22
Figure 17. Current Address Read.................................. 24
Figure 18. Random Read .............................................. 24
Figure 19. Sequential Read........................................... 24
Figure 20. 8-Pin Molded Small Outline Package (MW)
Package Number M08D ...................................... 25
Figure 21. Molded Dual-in-Line Package (N) Package
Number N08E...................................................... 26
Figure 22. 8-pin MLF Leadless Package ....................... 27
List of Tables
Table 1. Pin Names......................................................... 5
SA24C512 Datasheet
SAIFUN
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Block Diagram
Figure 1. SA24C512 Block Diagram
SA24C512 Datasheet
SAIFUN
5
Connection Diagram
SA24C512
1
2
3
4
8
7
6
5
A0
A1
NC
V
SS
V
CC
WP
SCL
SDA
Figure 2. SO, Package (MW), Dual-in-Line
Package (N), Top View
SA24C512
1
2
3
4
8
7
6
5
A0
A1
NC
V
SS
V
CC
SCL
SDA
Figure 3. Leadless Package (MLF), Top View
Note:
For more details, see Package Number N08E and M08D.
Table 1. Pin Names
Pin Name
Signal Name
Description
A0
Device Select Address
Input
Has an internal "weak" pull down so that when
left unconnected assumes logic LOW.
A1
Device Select Address
Input
Has an internal "weak" pull down so that when
left unconnected assumes logic LOW.
NC
No Connect
V
SS
Device Ground Input
SDA
IIC Data Input/Output
Open Collector/Drain type
SCL
IIC Clock Input
WP
Write Protect
Has an internal "weak" pull down so that when
left unconnected assumes logic LOW.
When LOW, Write is allowed to the memory
array.
When HIGH, Write is not allowed to the memory
array as defined in Write Protect (WP), page 14.
V
CC
Device Power Input
2.7 V to 3.6 V
Note:
No A2 pin (Pin 3) is provided. Treated as No Connect. Internal address
comparison assumes this pin to be 0 and hence the command code should
have corresponding bit set to 0.
SA24C512 Datasheet
SAIFUN
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Ordering Information
LZ
XX
C
24
SA
Letter
L
LZ
512
C
24
SA
Interface
Density
Voltage Operating Range
Description
2.7 V to 3.6 V
2.7 V to 3.6 V
< 0.7
A Standby Current
512 Kb with Write
Protect
CMOS EEPROM
Technology
IIC - 2 Wire
Saifun Non-Volatile
Memory
X
Blank
X
Tube
Tape and Reel
PP
Package
N
MW
MF
8-pin DIP
8-pin SOIC (200 mil)
8-lead MLF
F
Blank
F
Non-lead Free
Lead-free Leads
E
Blank
E
Temp. Range
0 to 70 C
-40 to +85 C
o
o
Figure 4. SA24C512 Ordering Information
SA24C512 Datasheet
SAIFUN
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Product Specifications
Absolute Maximum Ratings Operating Conditions
Ambient Storage Temperature
65
C to +150
C
All Input or Output Voltages with
Respect to Ground
4.5 V to -0.3 V
Lead Temperature
(Soldering, 10 seconds)
+300
C
ESD Rating
2000 V min.
ESD/Latchup Specification (JEDEC 8 Spec)
Human Body Model
Minimum 2 KV
Machine Model
Minimum 500 V
Latch up:
100 mA on all pins +125
C
Operating Conditions
Ambient Operating Temperature
SA24C512
SA24C512E
0
C to +70
C
-40
C to +85
C
SA24C512 Datasheet
SAIFUN
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DC Electrical Characteristics (VCC 2.7V to 3.6V)
Limits
Symbol
Parameter
Test Conditions
Min
Typ
(Notes)
Max
Units
f
SCL
= 100 kHz (Read)
2 3 mA
f
SCL
= 100 kHz (Write)
8 11 mA
f
SCL
=
400 KHZ (Read)
2 3 mA
f
SCL
=
400 kHz (Write)
8 11 mA
f
SCL
= 1.7 MHz (Read)
5 7 mA
f
SCL
=
1.7 MHz (Write)
8 11 mA
f
SCL
= 3.4 MHz (Read)
5 7 mA
I
CCA
Active Power Supply
Current
f
SCL
= 3.4 MHz (Write)
8 11 mA
I
SB
Standby Current (L)
V
IN
= GND
or
V
CC
0.5 1
A
Standby Current (LZ)
V
IN
= GND
or
V
CC
0.2 0.7
A
=
I
IL
Input Leakage Current
V
IN
= GND
to
V
CC
0.1 1
A
I
OL
Output Leakage
Current
V
OUT
= GND
to
V
CC
0.1 1
A
V
IL
Input Low Voltage
-0.3
V
CC
x
0.3 V
V
IH
Input High Voltage
V
CC
x 0.7
V
CC
+ 0.5
V
V
OL
Output Low Voltage
I
OL
= 3 mA
0.4 V
Notes
(1) Typical values are TA = 25
C and nominal supply voltage of 3 volts.
(2) Write frequency is 50 Hz.
Capacitance
T
A
= +25
C, f = 100/400 kHz/1.7 MHz/3.4 MHz, V
CC
= 3V
(Note 2)
Symbol
Test
Conditions
Max
Units
C
I/O
Input/Output
Capacitance (SDA)
V
I/O
=
0V 8
pF
C
IN
Input
Capacitance
(A0, A1, A2, SCL)
V
IN
= 0V
6
pF
Notes:
(1) This parameter is periodically sampled and not 100% tested.
(2) Typical values are T
A
= 25
C and nominal supply voltage of 3 volts.
SA24C512 Datasheet
SAIFUN
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AC Test Conditions
Input Pulse Levels
V
CC
x 0.1 to V
CC
x 0.9
Input Rise and Fall Times
10 ns
Input & Output Timing
Levels
V
CC
x 0.3 to V
CC
x 0.7
Output Load
1 TTL Gate and C
L
= 100 pF
AC Testing Input/Output Waveforms
Figure 5. AC Testing Input/Output Waveforms
AC Characteristics (V
CC
2.7V to 3.6V)
100 kHz
400 kHz
1.7 MHz
3.4 MHz
Symbol
Parameter
Min
Max
Min
Max
Min
Max
Min
Max
Units
f
SCL
SCL
Clock
Frequency 100 400 1700 3400 kHz
t
LOW
Clock
Low
Period 4700 1300 320 160
ns
t
HIGH
Clock
High
Period 4000 600 120 60 ns
tSU:STA
START Condition
Setup Time (for a
Repeated START
Condition)
4700 600 160 160 ns
t
HD:STA
START
Condition
Hold Time (for a
Repeated START
Condition)
4000 600 160 160 ns
t
SU:STO
STOP
Condition
Setup Time
4000 600 160 160 ns
t
RDA
SDA Rise Time
(depend on external
pull-up)
1000 300 20 170 10 85 ns
t
FDA
SDA
Fall
Time
300 300
20 170 10 85 ns
t
RCL
SCL Rise Time
(depend on external
pull-up)
1000 300 20 80 10 40 ns
t
FCL
SCL
Fall
Time
300 300
20 80 10 40 ns
t
RCL1
SCL Rise Time after
repeated START or
after ACK bit
NA NA NA 20 160 10 80 ns
t
SU:DAT
Data
in
Setup
Time 250 100 20 20 ns
t
HD:DAT
Data
in
Hold
Time 0 0 0 0 ns
t
DH
Data Out Hold Time
300
100
0
0
ns
SA24C512 Datasheet
SAIFUN
10
100 kHz
400 kHz
1.7 MHz
3.4 MHz
Symbol
Parameter
Min
Max
Min
Max
Min
Max
Min
Max
Units
T
I
Noise
Suppression
Time Constant at
SCL, SDA Inputs
(Minimum V
IN
Pulse
width)
50 50 10 10 ns
t
AA
SCL Low to SDA Data
Out Valid
300
1
3500 100
1
900 0 170 0 85 ns
t
BUF
Time the Bus Must Be
Free Before a New
Transmission Can
Start
4700 1300 320 160
ns
t
WR
Write
Cycle
Time
10 10 10 10 ms
Endurance
1
million
2
Cycles
1
The minimum value is defined to bridge the undefined part between V
IH
and V
IL
of the falling edge of SCL. The standard
number is 0 ns.
2
This parameter is not tested but ensured by characterization.
Bus Timing
Figure 6. Bus Timing
SA24C512 Datasheet
SAIFUN
11
Write Cycle Timing
Figure 7. Write Cycle Timing
Note:
The Write cycle time (t
WR
) is the time from a valid STOP condition of a Write
sequence to the end of the internal erase/program cycle.
Typical System Configuration
Figure 8. Typical System Configuration
Note:
Due to the open-drain configuration of SDA and SCL, a bus-level pull-up resistor
is called for, (typical value = 4.7k
).
SA24C512 Datasheet
SAIFUN
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Background Information
(IIC Bus)
Extended IIC specification is an extension
of the Standard IIC specification, which
enables addressing of EEPROMs with
more than 15 Kbits of memory on an IIC
bus. The difference between the two
specifications is that the Extended IIC
specification defines two bytes of "Array
Address" information, while the Standard
IIC specification defines only one. All other
aspects are identical between the two
specifications. Using two bytes of Array
Address and two address signals (A1 and
A0), it is now possible to address up to 4
Mbits (2
8
2
8
2
2
8 = 2 Mbits) of memory
on an IIC bus.
Note that due to format difference, it is not
possible to have both peripherals that
follow the Standard IIC specification (e.g.,
16-Kbit EEPROM) and peripherals that
follow the Extended IIC specification (e.g.,
512-Kbit EEPROM) on a common IIC bus.
The IIC bus allows synchronous
bidirectional communication between a
transmitter and a receiver using a Clock
signal (SCL) and a Data signal (SDA).
Additionally, there are two Address signals
(A1 and A0) that collectively serve as a
"chip select signal" to a device (e.g.,
EEPROM) on the bus.
All communication on the IIC bus must be
started with a valid START condition by a
master, followed by transmittal by the
master of byte(s) of information
(Address/Data). For every byte of
information received, the addressed
receiver provides a valid Acknowledge
pulse to further continue the
communication unless the receiver intends
to discontinue the communication.
Depending on the direction of transfer
(Write or Read), the receiver can be either
a slave or the master. A typical IIC
communication concludes with a STOP
condition (by the master).
Addressing an EEPROM memory location
involves sending a command string with
the following information:
[DEVICE TYPE]--[DEVICE/PAGE BLOCK
SELECTION]--[R/W BIT]--[ARRAY
ADDRESS#1]--[ARRAY ADDRESS#0]
Slave Address
The slave address is an 8-bit information
consisting of a Device type field (4 bits),
Device/Page block selection field (3 bits)
and Read/Write bit (1 bit).
Figure 9 Slave Address
SA24C512 Datasheet
SAIFUN
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Device Type
The IIC bus is designed to support a
variety of devices, such as RAMs,
EPROMs, and so on., along with
EEPROMS. To properly identify various
devices on the IIC bus, a 4-bit "Device
Type" identifier string is used. For
EEPROMS, this 4-bit string is 1-0-1-0.
Every IIC device on the bus internally
compares this 4-bit string to its own
"Device Type" string to ensure proper
device selection.
Device/Page Block Selection
When multiple devices of the same type
(e.g., multiple EEPROMS) are present on
the IIC bus, the A1 and A0 address
information bits are used in device
selection. Every IIC device on the bus
internally compares this 3-bit string to its
own physical configuration (A1 and A0
pins) to ensure proper device selection.
This comparison is in addition to the
"Device Type" comparison.
In addition to selecting an EEPROM, these
3 bits are also used to select a "page
block" within the selected EEPROM. Each
page block is 512 Kbits (64 KBytes) in size.
If an EEPROM contains more than one
page block, the selection of a page block
within the EEPROM is by using A1 and A0
bits.
Read/Write Bit
Last bit of the slave address indicates if the
intended access is Read or Write. If the bit
is 1, the access is Read; if it is 0, the
access is Write.
Acknowledge
Acknowledge is an active LOW pulse on
the SDA line driven by an addressed
receiver to the addressing transmitter to
indicate receipt of 8 bits of data. The
receiver provides an ACK pulse for every 8
bits of data received. This handshake
mechanism is done as follows: After
transmitting 8 bits of data, the transmitter
releases the SDA line and waits for the
ACK pulse. The addressed receiver, if
present, drives the ACK pulse on the SDA
line during the ninth clock and releases the
SDA line back (to the transmitter). Refer to
Figure 14.
Array Address#1
This is an 8-bit information containing the
most significant 8 bits of the 16-bit memory
array address of a location to be selected
within a page block of the device.
Array Address#0
This is an 8-bit information containing the
least significant 8-bits of 16-bit memory
array address of a location to be selected
within a page block of the device.
SA24C512 Datasheet
SAIFUN
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Pin Descriptions
Serial Clock (SCL)
The SCL input is used to clock all data into
and out of the device.
Serial Data (SDA)
SDA is a bidirectional pin used to transfer
data into and out of the device. It is an
open drain output and may be wireORed
with any number of open drain or open
collector outputs.
Write Protect (WP)
Choice 1: Full Array Write Protect
If pulled HIGH, Write operations will not be
executed. READ operations are possible. If
pulled LOW, normal operation is enabled,
READ/WRITE over the entire memory is
possible.
This feature allows the user to assign the
entire memory as ROM, which can be
protected against accidental programming.
When Write is disabled, the slave address
and word address will be acknowledged
but data will not be acknowledged.
This pin has an internal pull-down circuit.
However, on systems where write
protection is not required it is
recommended that this pin be tied to V
SS
.
Write Protection Truth Table
WP
Pin
"Less Than"
Comparison
T/B Bit
Write
Allowed
1 YES 0 NO
1 NO 0
YES
1 YES 1 YES
1 NO 1 NO
0 Don't
Care
Don't
Care
YES
SA24C512 Datasheet
SAIFUN
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Choice 2: Programmable Write Protect
(1)
The Programmable Write protection is available to customers by contacting a Sales
Representative. An internal 8-bit wide internal NV-latch is used, with the following definition:
1
Predefined on Sort. Not a user command.
Example
(512K )
Write Protection
Area
NV-Latch Bit
Setting - Bits [7:0]
Result
1 Full
Array
(0x0000 - 0xFFFF)
X-0-0-0-0-0-0-1
Address bits (A15:A10) issued during the Write command
are compared against bits[6:0] of this NV-Latch. Since bit[0]
of this NV-Latch is set to 1, Write is not allowed as long as
the comparison results in "greater than or equal to" status.
2 Bottom
Half
(0x0000 - 0x7FFF)
X-1-0-0-0-0-0-0
Same as example 1.
3 Bottom
Quadrant
(0x0000 - 0x3FFF)
X-0-1-0-0-0-0-0
Same as example 1.
4 Top
Quadrant
(0xFFF - oxC000)
X-1-1-0-0-0-0-1
Address bits (A15:A10) issued during the Write command
are compared against bits[6:0] of this NV-Latch. Since bit[0]
of this NV-Latch is set to 1, Write is allowed as long as the
comparison results in "greater than or equal to" status.
5 Top
Half
(0xFFF - 0x8000)
X-1-0-0-0-0-0-1
Same as example 4.
6
No Write Protection
X-0-0-0-0-0-0-0
Same as example 4.
SA24C512 Datasheet
SAIFUN
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Device Selection Inputs A1 and
A0 (as Appropriate)
These inputs collectively serve as a "chip
select" signal to an EEPROM when
multiple EEPROMs are present on the
same IIC bus. Hence these inputs, if
present, should be connected to either V
CC
or V
SS
in a unique manner to enable proper
selection of an EEPROM among multiple
EEPROMs. During a typical addressing
sequence, every EEPROM on the IIC bus
compares the configuration of these inputs
to the respective 3-bit "Device/Page block
selection" information (part of the slave
address) to determine a valid selection. For
example, if the 3-bit "Device/Page block
selection" is 1-0-1, the EEPROM whose
"Device Selection inputs" (A1 and A0) are
connected to V
CC
-V
SS
-V
CC
, respectively, is
selected.
Only A1 and A0 are provided on the
SA24C512, which means that the
corresponding A2 bit in the "Device/Page
block selection" should be set to 0 during
all access to the device. These two pins
have a weak internal pull-down circuit.
SA24C512 Datasheet
SAIFUN
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Device Operation
The SA24C512 supports a bidirectional
bus-oriented protocol. The protocol defines
any device that sends data onto the bus as
a transmitter and the receiving device as
the receiver. The device controlling the
transfer is the master and the device that is
controlled is the slave. The master will
always initiate data transfers and provide
the clock for both transmit and receive
operations. Therefore, the SA24C512 will
be considered a slave in all applications.
Clock and Data Conventions
Data states on the SDA line can change
only during SCL LOW. SDA state changes
during SCL HIGH are reserved for
indicating START and STOP conditions.
Refer to Figure 12.
START Condition
All commands are preceded by the START
condition, which is a HIGH-to-LOW
transition of SDA when SCL is HIGH. The
SA24C512 continuously monitors the SDA
and SCL lines for the START condition and
will not respond to any command until this
condition has been met.
Refer to Figure 13.
STOP Condition
All communications are terminated by a
STOP condition, which is a LOW-to-HIGH
transition of SDA when SCL is HIGH. The
STOP condition is also used by the
SA24C512 to place the device in the
standby power mode. Refer to Figure 13.
SA24C512 Array Addressing
During Read/Write operations, addressing
the EEPROM memory array involves in
providing two address bytes, "Word
Address 1" and "Word Address 0." The
"Word Address 1" byte contains the eight
most significant bits of the array address,
while "Word Address 0" byte contains the
eight least significant bits of the array
address.
SA24C512 Datasheet
SAIFUN
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Switching from F/S to HS Mode and Back
After reset and initialization, the device must be in Fast mode. The master on the bus can
choose to switch the connected slave devices to HS mode. The slave device must then
recognize the "S 00001XXX A" sequence and switch its internal circuit from Fast mode to
HS mode. Each device must recognize the STOP condition and switch back to Fast mode
Timings and flow are shown in the figures below.
Figure 10. Data Transfer in Hs-mode
SA24C512 Datasheet
SAIFUN
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Figure 11. A Complete Hs-mode Transfer
Figure 12. Data Validity
SA24C512 Datasheet
SAIFUN
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Figure 13. START and STOP Definition
Figure 14. Acknowledge Response from Receiver
SA24C512 Datasheet
SAIFUN
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Write Operations
Byte Write
Two bytes of address are required after the
slave address for a Byte Write operation.
These two bytes select one out of the 64K
locations in the memory. The master
provides these two address bytes and for
each address byte received, SA24C512
responds with an Acknowledge pulse. The
master then provides a byte of data to be
written into the memory. Upon receipt of
this data, the SA24C512 responds with an
Acknowledge pulse. The master then
terminates the transfer by generating a
STOP condition, at which time the
SA24C512 begins the internal Write cycle
to the memory. While the internal Write
cycle is in progress, the SA24C512 inputs
are disabled, and the device will not
respond to any requests from the master
for the duration of t
WR
. Refer to Figure 15
for the address, acknowledge and data
transfer sequence.
Page Write
To minimize Write cycle time, the
SA24C512 offers a Page Write feature,
which allows simultaneous programming of
up to 128 contiguous bytes. To facilitate
this feature, the memory array is organized
in terms of "pages." A page consists of 128
contiguous byte locations starting at every
128-Byte address boundary (for example,
starting at array address 0x0000, 0x0080,
0x0100, and so on).
The Page Write operation is confined to a
single page, which means that it will not
cross over to locations on the next page
but instead "rolls over" to the beginning of
the page whenever the end of a page is
reached and additional data bytes continue
to be provided. A Page Write operation can
be initiated to begin at any location within a
page (the starting address of the Page
Write operation need not be the starting
address of a page).
Page Write is initiated in the same manner
as the Byte Write operation, but instead of
terminating the cycle after transmitting the
first data byte, the master can further
transmit up to 127 more bytes. After the
receipt of each byte, the SA24C512 will
respond with an Acknowledge pulse,
increment the internal address counter to
the next address, and becomes ready to
accept the next data. If the master should
transmit more than 128 bytes prior to
generating the STOP condition, the
address counter will "roll over" and
previously loaded data will be re-loaded. As
with the Byte Write operation, all inputs are
disabled until completion of the internal
Write cycle. Refer to Figure 16 for the
address, acknowledge, and data transfer
sequence.
SA24C512 Datasheet
SAIFUN
22
Acknowledge Polling
Once the STOP condition is issued to
indicate the end of the host's Write
operation, the SA24C512 initiates the
internal Write cycle. ACK polling can be
initiated immediately, which involves
issuing the START condition followed by
the slave address for a Write operation. If
the SA24C512 is still busy with the Write
operation, no ACK will be returned. If the
SA24C512 has completed the Write
operation, an ACK will be returned and the
host can then proceed with the next Read
or Write operation.
Write Protection
Programming the memory will not take
place if the WP pin of the SA24C512 is
pulled HIGH. The SA24C512 will respond
to the slave and byte addresses, but will
not generate an Acknowledge after the first
byte of data has been received. Thus, the
program cycle will not be started when the
STOP condition is asserted.
Figure 15. Byte Write
Figure 16. Page Write
SA24C512 Datasheet
SAIFUN
23
Read Operations
Read operations are initiated in the same
manner as Write operations, with the
exception that the R/ W
bit of the slave
address is set to 1. There are three basic
Read operations: current address Read,
random Read and sequential Read.
Current Address Read
Internally, the SA24C512 contains an
address counter that maintains the address
of the last byte accessed, incremented by
1. Therefore, if the last access (either a
Read or Write) was to address n, the next
Read operation would access data from
address n + 1. Upon receipt of the slave
address with R/ W
set to 1, the SA24C512
issues an Acknowledge and transmits the
8-bit word. The master will not
acknowledge the transfer but does
generate a STOP condition, and therefore
the SA24C512 discontinues transmission.
Refer to Figure 17 for the address,
acknowledge and data transfer sequence.
Random Read
Random Read operations enable the
master to access any memory location in a
random manner. Prior to issuing the slave
address with the R/ W
bit set to 1, the
master must first perform a "dummy" Write
operation. The master issues the START
condition, the slave address with the
R/ W bit set to 0 and then the byte address
is read.
After the byte address is acknowledged,
the master immediately issues another
START condition and the slave address
with the R/ W bit set to 1. This will be
followed by an Acknowledge from the
SA24C512 and then by the 8-bit word. The
master will not acknowledge the transfer
but does generate the STOP condition,
and therefore the SA24C512 discontinues
transmission. Refer to Figure 18 for the
address, acknowledge, and data transfer
sequence.
Sequential Read
Sequential Reads can be initiated as either
a current address Read or random access
Read. The first word is transmitted in the
same manner as the other Read modes;
however, the master now responds with an
Acknowledge, indicating it requires
additional data. The SA24C512 continues
to output data for each Acknowledge
received. The Read operation is terminated
by the master not responding with an
Acknowledge or by generating a STOP
condition.
The data output is sequential with the data
from address n followed by the data from n
+ 1. The address counter for Read
operations increments all word address
bits, allowing the entire memory contents to
be serially read during one operation. After
the entire memory has been read, the
counter "rolls over" to the beginning of the
memory. The SA24C512 continues to
output data for each Acknowledge
received. Refer to Figure 19 for the
address, acknowledge, and data transfer
sequence.
SA24C512 Datasheet
SAIFUN
24
Figure 17. Current Address Read
Figure 18. Random Read
Figure 19. Sequential Read
SA24C512 Datasheet
SAIFUN
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Physical Dimensions
All measurements are in inches (millimeters), unless otherwise specified.
Figure 20. 8-Pin Molded Small Outline Package (MW) Package Number M08D
SA24C512 Datasheet
SAIFUN
26
Figure 21. Molded Dual-in-Line Package (N) Package Number N08E
SA24C512 Datasheet
SAIFUN
27
Figure 22. 8-pin MLF Leadless Package
SA24C512 Datasheet
SAIFUN
28
Contact Information
International Headquarters
United States
Saifun Semiconductors Ltd.
ELROD Building
45 Hamelach St.
Sappir Industrial Park
Netanya 42504
Israel
Tel.: +972-9-892-8444
Fax: +972-9-892-8445
Saifun Semiconductors Inc.
2350 Mission College Blvd.
Suite 1070
Santa Clara, CA 95054
U.S.A.
Tel: +1-408-982-5888
Fax: +1-408-982-5890
Email: tech_support@saifun.com
http://www.saifun.com
Revision History
Rev.
Date
Description of Change
0.0
5 Sept 2002
Initial Release
1.0
4-Aug-2003
Added MLF Package and minor format improvements
1.1
10-Sept 2003
Changed Endurance to 1 million cycles
Saifun Semiconductors Ltd. 2003
Saifun reserves the right, without notice, to change any of the products described in this guide, in order to improve functionality,
reliability or design. Saifun assumes no liability arising from the application or use of any product described in this guide; and
under its patent rights, gives no authorization for the use of this product or associated products. Saifun makes no warranty for use
of its products, other than expressly provided by Saifun in any applicable warranty. The Buyer will not hold Saifun responsible for
direct or indirect damages and expenses, as well as any claim of injury or death, associated with the unauthorized use, including
claims of manufacture or design negligence.
Saifun and Saifun NROM are trademarks or registered trademarks of Saifun Semiconductors Ltd. Other company and brand
products and service names are trademarks or registered trademarks of their respective holders.
Life Support Policy
Saifun's products are not authorized for use as critical components in life support devices or systems without the express written
approval of the President of Saifun Semiconductors Ltd. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical
implant into the body, or (b) support or sustain
life, and whose failure to perform, when properly
used in accordance with instructions for use
provided in the labeling, can be reasonably
expected to result in a significant injury to the
user.
2. A critical component is any component of a life
support device or system whose failure to
perform can be reasonably expected to cause the
failure of the life support device or system, or to
affect its safety or effectiveness.
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