STMICROELECTRONICS ST24W16M1TR

ST24C16, ST25C16
ST24W16, ST25W16
16 Kbit Serial I2C Bus EEPROM
with User-Defined Block Write Protection
1 MILLION ERASE/WRITE CYCLES, with
40 YEARS DATA RETENTION
SINGLE SUPPLY VOLTAGE:
– 4.5V to 5.5V for ST24x16 versions
– 2.5V to 5.5V for ST25x16 versions
HARDWARE WRITE CONTROL VERSIONS:
ST24W16 and ST25W16
TWO WIRE SERIAL INTERFACE, FULLY I2C
BUS COMPATIBLE
BYTE and MULTIBYTE WRITE (up to 8
BYTES) for the ST24C16
PAGE WRITE (up to 16 BYTES)
BYTE, RANDOM and SEQUENTIAL READ
MODES
SELF TIMED PROGRAMING CYCLE
AUTOMATIC ADDRESS INCREMENTING
ENHANCED ESD/LATCH UP
PERFORMANCES
DESCRIPTION
This specification covers a range of 16 Kbit I2C bus
EEPROM products, the ST24/25C16 and the
ST24/25W16. In the text, products are referred to
as ST24/25x16 where "x" is: "C" for Standard version and "W" for hardware Write Control version.
The ST24/25x16 are 16 Kbit electrically erasable
programmable memories (EEPROM), organized
as 8 blocks of 256 x8 bits. These are manufactured
in STMicroelectronics’s Hi-Endurance Advanced
CMOS technology which guarantees an endurTable 1. Signal Names
PRE
Write Protect Enable
PB0, PB1
Protect Block Select
SDA
Serial Data Address Input/Output
SCL
Serial Clock
MODE
Multybyte/Page Write Mode
(C version)
WC
Write Control (W version)
VCC
Supply Voltage
VSS
Ground
February 1999
8
8
1
1
PSDIP8 (B)
0.25mm Frame
SO8 (M)
150mil Width
Figure 1. Logic Diagram
VCC
2
PB0-PB1
PRE
SCL
SDA
ST24x16
ST25x16
MODE/WC*
VSS
AI00866B
Note: WC signal is only available for ST24/25W16 products.
1/17
ST24/25C16, ST24/25W16
Figure 2A. DIP Pin Connections
Figure 2B. SO8 Pin Connections
ST24x16
ST25x16
PRE
PB0
PB1
VSS
1
2
3
4
8
7
6
5
ST24x16
ST25x16
VCC
MODE/WC
SCL
SDA
PRE
PB0
PB1
VSS
AI00867B
1
2
3
4
8
7
6
5
VCC
MODE/WC
SCL
SDA
AI00500B
Table 2. Absolute Maximum Ratings (1)
Symbol
Value
Unit
Ambient Operating Temperature
–40 to 125
°C
TSTG
Storage Temperature
–65 to 150
°C
TLEAD
Lead Temperature, Soldering
215
260
°C
TA
Parameter
(SO8)
(PSDIP8)
40 sec
10 sec
VIO
Input or Output Voltages
–0.6 to 6.5
V
VCC
Supply Voltage
–0.3 to 6.5
V
VESD
Electrostatic Discharge Voltage (Human Body model) (2)
4000
V
Electrostatic Discharge Voltage (Machine model) (3)
500
V
Notes: 1. Except for the rating "Operating Temperature Range", stresses above those listed in the Table "Absolute Maximum Ratings"
may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other
conditions above those indicated in the Operating sections of this specification is not implied. Exposure to Absolute Maximum
Rating conditions for extended periods may affect device reliability. Refer also to the STMicroelectronics SURE Program and
other relevant quality documents.
2. 100pF through 1500Ω; MIL-STD-883C, 3015.7
3. 200pF through 0Ω; EIAJ IC-121 (condition C)
DESCRIPTION (cont’d)
ance of one million erase/write cycles with a data
retention of 40 years. The ST25x16 operates with
a power supply value as low as 2.5V. Both Plastic
Dual-in-Line and Plastic Small Outline packages
are available.
The memories are compatible with the I2C standard, two wire serial interface which uses a bi-directional data bus and serial clock. The memories
2/17
carry a built-in 4 bit, unique device identification
code (1010) corresponding to the I2C bus definition. The memories behave as slave devices in the
I2C protocol with all memory operations synchronized by the serial clock. Read and write operations
are initiated by a START condition generated by the
bus master. The START condition is followed by a
stream of 4 bits (identification code 1010), 3 block
select bits, plus one read/write bit and terminated
by an acknowledge bit. When writing data to the
ST24/25C16, ST24/25W16
Table 3. Device Select Code
Device Code
Memory MSB Addresses
RW
Bit
b7
b6
b5
b4
b3
b2
b1
b0
Device Select
1
0
1
0
A10
A9
A8
RW
Note: The MSB b7 is sent first.
Table 4. Operating Modes
Mode
Current Address Read
Random Address Read
RW bit
MODE pin
Bytes
’1’
X
1
X
1
’0’
’1’
Initial Sequence
START, Device Select, RW = ’1’
START, Device Select, RW = ’0’, Address,
reSTART, Device Select, RW = ’1’
Sequential Read
’1’
X
1 to 2048
As CURRENT or RANDOM Mode
Byte Write
’0’
X
1
START, Device Select, RW = ’0’
Multibyte Write
’0’
VIH
8
START, Device Select, RW = ’0’
Page Write
’0’
VIL
16
START, Device Select, RW = ’0’
Note: X = VIH or VIL.
memory it responds to the 8 bits received by asserting an acknowledge bit during the 9th bit time.
When data is read by the bus master, it acknowledges the receipt of the data bytes in the same
way. Data transfers are terminated with a STOP
condition.
Data in the 4 upper blocks of the memory may be
write protected. The protected area is programmable to start on any 16 byte boundary. The block in
which the protection starts is selected by the input
pins PB0, PB1. Protection is enabled by setting a
Protect Flag bit when the PRE input pin is driven
High.
Power On Reset: VCC lock out write protect. In
order to prevent data corruption and inadvertent
write operations during power up, a Power On
Reset (POR) circuit is implemented. Untill the VCC
voltage has reached the POR threshold value, the
internal reset is active: all operations are disabled
and the device will not respond to any command.
In the same way, when VCC drops down from the
operating voltage to below the POR threshold
value, all operations are disabled and the device
will not respond to any command. A stable VCC
must be applied before applying any logic signal.
3/17
ST24/25C16, ST24/25W16
SIGNALS DESCRIPTION
Serial Clock (SCL). The SCL input signal is used
to synchronise all data in and out of the memory. A
resistor can be connected from the SCL line to VCC
to act as a pull up (see Figure 3).
Serial Data (SDA). The SDA signal is bi-directional
and is used to transfer data in or out of the memory.
It is an open drain output that may be wire-OR’ed
with other open drain or open collector signals on
the bus. A resistor must be connected from the SDA
bus line to VCC to act as pull up (see Figure 3).
Protected Block Select (PB0, PB1). PB0 and PB1
input signals select the block in the upper part of
the memory where write protection starts. These
inputs have a CMOS compatible input level.
Protect Enable (PRE). The PRE input signal, in
addition to the status of the Block Address Pointer
bit (b2, location 7FFh as in Figure 7), sets the PRE
write protection active.
Mode (MODE). The MODE input is available on pin
7 (see also WC feature) and may be driven dynamically. It must be at VIL or VIH for the Byte Write
mode, VIH for Multibyte Write mode or VIL for Page
Write mode. When unconnected, the MODE input
is internally read as VIH (Multibyte Write mode).
Write Control (WC). An hardware Write Control
feature is offered only for ST24W16 and ST25W16
versions on pin 7. This feature is usefull to protect
the contents of the memory from any erroneous
erase/write cycle. The Write Control signal is used
to enable (WC at VIH) or disable (WC at VIL) the
internal write protection. When unconnected, the
WC input is internally read as VIL. The devices with
this Write Control feature no longer supports the
Multibyte Write mode of operation, however all
other write modes are fully supported.
Refer to the AN404 Application Note for more detailed information about Write Control feature.
Figure 3. Maximum RL Value versus Bus Capacitance (CBUS) for an I2C Bus
20
VCC
16
RL max (kΩ)
RL
12
RL
SDA
MASTER
CBUS
SCL
8
CBUS
4
VCC = 5V
0
100
200
CBUS (pF)
4/17
300
400
AI01100
ST24/25C16, ST24/25W16
Table 5. Input Parameters (1) (TA = 25 °C, f = 100 kHz )
Symbol
Parameter
Test Condition
Min
Max
Unit
CIN
Input Capacitance (SDA)
8
pF
CIN
Input Capacitance (other pins)
6
pF
20
kΩ
ZWCL
WC Input Impedance (ST24/25W16)
VIN ≤ 0.3 VCC
5
ZWCH
WC Input Impedance (ST24/25W16)
VIN ≥ 0.7 VCC
500
tLP
Low-pass filter input time constant
(SDA and SCL)
kΩ
100
ns
Max
Unit
Note: 1. Sampled only, not 100% tested.
Table 6. DC Characteristics
(TA = 0 to 70 °C or –40 to 85 °C; VCC = 4.5V to 5.5V or 2.5V to 5.5V)
Symbol
Parameter
Test Condition
ILI
Input Leakage Current
0V ≤ VIN ≤ VCC
±2
µA
ILO
Output Leakage Current
0V ≤ VOUT ≤ VCC
SDA in Hi-Z
±2
µA
Supply Current (ST24 series)
VCC = 5V, fC = 100kHz
(Rise/Fall time < 10ns)
2
mA
Supply Current (ST25 series)
VCC = 2.5V, fC = 100kHz
1
mA
VIN = VSS or VCC,
VCC = 5V
100
µA
VIN = VSS or VCC,
VCC = 5V, fC = 100kHz
300
µA
VIN = VSS or VCC,
VCC = 2.5V
5
µA
VIN = VSS or VCC,
VCC = 2.5V, fC = 100kHz
50
µA
ICC
ICC1
ICC2
Supply Current (Standby)
(ST24 series)
Supply Current (Standby)
(ST25 series)
Min
VIL
Input Low Voltage (SCL, SDA)
–0.3
0.3 VCC
V
VIH
Input High Voltage (SCL, SDA)
0.7 VCC
VCC + 1
V
VIL
Input Low Voltage
(PB0 - PB1, PRE, MODE, WC)
–0.3
0.5
V
VIH
Input High Voltage
(PB0 - PB1, PRE, MODE, WC)
VCC – 0.5
VCC + 1
V
VOL
Output Low Voltage (ST24 series)
IOL = 3mA, VCC = 5V
0.4
V
Output Low Voltage (ST25 series)
IOL = 2.1mA, VCC = 2.5V
0.4
V
5/17
ST24/25C16, ST24/25W16
Table 7. AC Characteristics
(TA = 0 to 70 °C or –40 to 85 °C; VCC = 4.5V to 5.5V or 2.5V to 5.5V)
Symbol
Alt
tCH1CH2
tR
tCL1CL2
Max
Unit
Clock Rise Time
1
µs
tF
Clock Fall Time
300
ns
tDH1DH2
tR
Input Rise Time
1
µs
tDL1DL1
tF
Input Fall Time
300
ns
tCHDX
(1)
tSU:STA
Parameter
Min
4.7
µs
Clock Pulse Width High
4
µs
Clock High to Input Transition
tCHCL
tHIGH
tDLCL
tHD:STA
Input Low to Clock Low (START)
4
µs
tCLDX
tHD:DAT
Clock Low to Input Transition
0
µs
tCLCH
tLOW
Clock Pulse Width Low
4.7
µs
tDXCX
tSU:DAT
Input Transition to Clock Transition
250
ns
tCHDH
tSU:STO
Clock High to Input High (STOP)
4.7
µs
tDHDL
tBUF
Input High to Input Low (Bus Free)
4.7
µs
tAA
Clock Low to Next Data Out Valid
0.3
tCLQX
tDH
Data Out Hold Time
300
fC
fSCL
Clock Frequency
100
kHz
tWR
Write Time
10
ms
tCLQV
tW
(2)
(3)
3.5
µs
ns
Notes: 1. For a reSTART condition, or following a write cycle.
2. The minimum value delays the falling/rising edge of SDA away from SCL = 1 in order to avoid unwanted START and/or STOP
conditions.
3. In the Multibyte Write mode only, if accessed bytes are on two consecutive 8 bytes rows (5 address MSB are not constant)
the maximum programming time is doubled to 20ms.
Table 8. AC Measurement Conditions
Input Rise and Fall Times
≤ 50ns
Input Pulse Voltages
0.2VCC to 0.8VCC
Input and Output Timing Ref.
Voltages
0.3VCC to 0.7VCC
Figure 4. AC Testing Input Output Waveforms
0.8VCC
0.2VCC
0.7VCC
0.3VCC
AI00825
6/17
DEVICE OPERATION
I2C Bus Background
The ST24/25x16 support the I2C protocol. This
protocol defines any device that sends data onto
the bus as a transmitter and any device that reads
the data as a receiver. The device that controls the
data transfer is known as the master and the other
as the slave. The master will always initiate a data
transfer and will provide the serial clock for synchronisation. The ST24/25x16 are always slave
devices in all communications.
Start Condition. START is identified by a high to
low transition of the SDA line while the clock SCL
is stable in the high state. A START condition must
precede any command for data transfer. Except
during a programming cycle, the ST24/25x16 continuously monitor the SDA and SCL signals for a
START condition and will not respond unless one
is given.
ST24/25C16, ST24/25W16
Figure 5. AC Waveforms
tCHCL
tCLCH
SCL
tDLCL
tDXCX
tCHDH
SDA IN
tCHDX
START
CONDITION
tCLDX
tDHDL
SDA
INPUT
SDA
CHANGE
STOP &
BUS FREE
SCL
tCLQV
tCLQX
DATA VALID
SDA OUT
DATA OUTPUT
SCL
tW
SDA IN
tCHDH
STOP
CONDITION
tCHDX
WRITE CYCLE
START
CONDITION
AI00795B
7/17
ST24/25C16, ST24/25W16
Figure 6. I2C Bus Protocol
SCL
SDA
START
CONDITION
SCL
1
SDA
MSB
SDA
INPUT
2
SDA
CHANGE
STOP
CONDITION
3
7
8
9
ACK
START
CONDITION
SCL
1
SDA
MSB
2
3
7
8
9
ACK
STOP
CONDITION
AI00792
Stop Condition. STOP is identified by a low to high
transition of the SDA line while the clock SCL is
stable in the high state. A STOP condition terminates communication between the ST24/25x16
and the bus master. A STOP condition at the end
of a Read command forces the standby state. A
STOP condition at the end of a Write command
triggers the internal EEPROM write cycle.
Acknowledge Bit (ACK). An acknowledge signal
is used to indicate a successful data transfer. The
bus transmitter, either master or slave, will release
the SDA bus after sending 8 bits of data. During the
9th clock pulse period the receiver pulls the SDA
bus low to acknowledge the receipt of the 8 bits of
data.
8/17
Data Input. During data input the ST24/25x16
samples the SDA bus signal on the rising edge of
the clock SCL. Note that for correct device operation the SDA signal must be stable during the clock
low to high transition and the data must change
ONLY when the SCL line is low.
Memory Addressing. To start communication between the bus master and the slave ST24/25x16,
the master must initiate a START condition. The 8
bits sent after a START condition are made up of a
device select of 4 bits that identifie the device type
(1010), 3 Block select bits and one bit for a READ
(RW = 1) or WRITE (RW = 0) operation.
There are three modes both for read and write.
They are summarised in Table 4 and described
hereafter. A communication between the master
and the slave is ended with a STOP condition.
ST24/25C16, ST24/25W16
Figure 7. Memory Protection
PB1
Block
Select
PB0
1
Protect Location
16 byte
boundary
address
b7
7FFh
Protect Flag
Enable = 0
Disable = 1
b4
PB1 PB0
b2
0
X
X
Block 7
1
1
Block 6
1
0
Block 5
0
1
Block 4
0
0
700h
600h
500h
400h
AI00870B
Write Operations
The Multibyte Write mode (only available on the
ST24/25C16 versions) is selected when the MODE
pin is at VIH and the Page Write mode when MODE
pin is at VIL. The MODE pin may be driven dynamically with CMOS input levels.
Following a START condition the master sends a
device select code with the RW bit reset to ’0’. The
memory acknowledges this and waits for a byte
address. The byte address of 8 bits provides access to any of the 256 bytes of one memory block.
After receipt of the byte address the device again
responds with an acknowledge.
For the ST24/25W16 versions, any write command
with WC = ’1’ (during a period of time from the
START condition untill the end of the Byte Address)
will not modify data and will NOT be acknowledged
on data bytes, as in Figure 10.
Byte Write. In the Byte Write mode the master
sends one data byte, which is acknowledged by the
memory. The master then terminates the transfer
by generating a STOP condition. The Write mode
is independant of the state of the MODE pin which
could be left floating if only this mode was to be
used. However it is not a recommended operating
mode, as this pin has to be connected to either VIH
or VIL, to minimize the stand-by current.
Multibyte Write (ST24/25C16 only). For the Multibyte Write mode, the MODE pin must be at VIH.
The Multibyte Write mode can be started from any
address in the memory. The master sends from one
up to 8 bytes of data, which are each acknowledged
by the memory. The transfer is terminated by the
master generating a STOP condition. The duration
of the write cycle is tW = 10ms maximum except
when bytes are accessed on 2 contiguous rows
(one row is 16 bytes), the programming time is then
doubled to a maximum of 20ms. Writing more than
8 bytes in the Multibyte Write mode may modify
data bytes in an adjacent row (one row is 16 bytes
long). However, the Multibyte Write can properly
write up to 16 consecutive bytes only if the first
address of these 16 bytes is the first address of the
row, the 15 following bytes being written in the 15
following bytes of this same row.
9/17
ST24/25C16, ST24/25W16
Page Write. For the Page Write mode, the MODE
pin must be at VIL. The Page Write mode allows up
to 16 bytes to be written in a single write cycle,
provided that they are all located in the same ’row’
in the memory: that is the same Block Address bits
(b3, b2, b1 of Device Select code in Table 3) and
the same 4 MSBs in the Byte Address. The master
sends one up to 16 bytes of data, which are each
acknowledged by the memory. After each byte is
transfered, the internal byte address counter (4
Least Significant Bits only) is incremented. The
transfer is terminated by the master generating a
STOP condition. Care must be taken to avoid address counter ’roll-over’ which could result in data
being overwritten. Note that for any write mode, the
generation by the master of the STOP condition
starts the internal memory program cycle. All inputs
are disabled until the completion of this cycle and
the memory will not respond to any request.
Minimizing System Delay by Polling On ACK.
During the internal Write cycle, the memory disconnects itself from the bus in order to copy the data
from the internal latches to the memory cells. The
maximum value of the Write time (tW) is given in the
AC Characteristics table, this timing value may be
reduced by an ACK polling sequence issued by the
master.
The sequence is:
– Initial condition: a Write is in progress (see Figure 8).
– Step 1: the Master issues a START condition
followed by a Device Select byte (1st byte of
the new instruction).
– Step 2: if the memory is internally writing, no
ACK will be returned. The Master goes back
to Step1. If the memory has terminated the internal writing, it will issue an ACK indicating
that the memory is ready to receive the second part of the instruction (the first byte of this
instruction was already sent during Step 1).
Figure 8. Write Cycle Polling using ACK
WRITE Cycle
in Progress
START Condition
DEVICE SELECT
with RW = 0
NO
First byte of instruction
with RW = 0 already
decoded by ST24xxx
ACK
Returned
YES
NO
Next
Operation is
Addressing the
Memory
YES
Send
Byte Address
ReSTART
STOP
Proceed
WRITE Operation
Proceed
Random Address
READ Operation
AI01099B
10/17
ST24/25C16, ST24/25W16
Write Protection. Data in the upper four blocks of
256 bytes of the memory may be write protected.
The memory is write protected between a boundary
address and the top of memory (address
7FFh).The boundary address is user defined by
writing it in the Block Address Pointer (location
7FFh).
The Block Address Pointer is an 8 bit EEPROM
register located at the address 7FFh. It is composed by 4 MSBs Address Pointer, which defines
the bottom boundary address, and 4 LSBs which
must be programmed at ’0’. This Address Pointer
can therefore address a boundary by page of 16
bytes.
The block in which the Block Address Pointer defines the boundary of the write protected memory
is defined by the logic level applied on the PB1 and
PB0 input pins:
– PB1 =’0’and PB0 =’0’ select block 4
– PB1 =’0’and PB0 =’1’ select block 5
– PB1 =’1’and PB0 =’0’ select block 6
– PB1 =’1’and PB0 =’1’ select block 7
The following sequence should be used to set the
Write Protection:
– write the data to be protected into the top of
the memory, up to, but not including, location
7FFh;
– select the block by hardwiring the signals PB0
& PB1;
– set the protection by writing the correct bottom
boundary address in the Address Pointer (4
MSBs of location 7FFh) with bit b2 (Protect
Flag) set to ’0’.
Note that for a correct fonctionality of the memory,
all the 4 LSBs of the Block Address Pointer must
also be programmed at ’0’. The area will be protected when the PRE input is taken High.
Remark: The Write Protection is active if and only
if the PRE input pin is driven High and the bit 2 of
location 7FFh is set to ’0’. In all the other cases, the
memory Block will not be protected. While the PRE
input pin is read at ’0’ by the memory, the location
7FFh can be used as a normal EEPROM byte.
Caution: Special attention must be used when
using the protect mode together with the Multibyte
Write mode (MODE input pin High). If the Multibyte
Write starts at the location right below the first byte
of the Write Protected area, then the instruction will
write over the first 7 bytes of the Write Protected
area. The area protected is therefore smaller than
the content defined in the location 7FFh, by 7 bytes.
This does not apply to the Page Write mode as the
address counter ’roll-over’ and thus cannot go
above the 16 bytes lower boundary of the protected
area.
Figure 9. Write Modes Sequence (ST24/25C16)
ACK
BYTE ADDR
DATA IN
R/W
ACK
START
DEV SEL
ACK
BYTE ADDR
ACK
DATA IN 1
DATA IN 2
R/W
ACK
ACK
DATA IN N
STOP
MULTIBYTE
AND
PAGE WRITE
ACK
STOP
DEV SEL
START
BYTE WRITE
ACK
AI00793
11/17
ST24/25C16, ST24/25W16
Figure 10. Write Modes Sequence with Write Control = 1 (ST24/25W16)
WC
ACK
BYTE ADDR
NO ACK
DATA IN
STOP
DEV SEL
START
BYTE WRITE
ACK
R/W
WC
ACK
DEV SEL
START
PAGE WRITE
ACK
BYTE ADDR
NO ACK
DATA IN 1
DATA IN 2
R/W
WC (cont'd)
NO ACK
DATA IN N
STOP
PAGE WRITE
(cont'd)
NO ACK
AI01161B
Read Operation
Read operations are independent of the state of the
MODE signal. On delivery, the memory content is
set at all "1’s" (or FFh).
Current Address Read. The memory has an internal byte address counter. Each time a byte is
read, this counter is incremented. For the Current
Address Read mode, following a START condition,
the master sends a memory address with the RW
bit set to ’1’. The memory acknowledges this and
outputs the byte addressed by the internal byte
address counter. This counter is then incremented.
The master does NOT acknowledge the byte output, but terminates the transfer with a STOP condition.
12/17
Random Address Read. A dummy write is performed to load the address into the address counter
(see Figure 11). This is followed by another START
condition from the master and the byte address
repeated with the RW bit set to ’1’. The memory
acknowledges this and outputs the byte addressed. The master does NOT acknowledge the
byte output, but terminates the transfer with a
STOP condition.
Sequential Read. This mode can be initiated with
either a Current Address Read or a Random Address Read. However, in this case the master
DOES acknowledge the data byte output and the
memory continues to output the next byte in sequence. To terminate the stream of bytes, the
master must NOT acknowledge the last byte out-
ST24/25C16, ST24/25W16
Figure 11. Read Modes Sequence
ACK
DATA OUT
STOP
START
DEV SEL
R/W
ACK
RANDOM
ADDRESS
READ
BYTE ADDR
R/W
ACK
START
DEV SEL
DATA OUT
R/W
ACK
ACK
DATA OUT 1
NO ACK
DATA OUT N
R/W
ACK
START
DEV SEL *
ACK
BYTE ADDR
R/W
ACK
ACK
DEV SEL *
START
SEQUENTIAL
RANDOM
READ
NO ACK
STOP
SEQUENTIAL
CURRENT
READ
ACK
DEV SEL *
START
START
DEV SEL *
ACK
STOP
CURRENT
ADDRESS
READ
NO ACK
ACK
DATA OUT 1
R/W
NO ACK
STOP
DATA OUT N
AI00794C
Note: * The 7 Most Significant bits of DEV SEL bytes of a Random Read (1st byte and 3rd byte) must be identical.
put, but MUST generate a STOP condition. The
output data is from consecutive byte addresses,
with the internal byte address counter automatically incremented after each byte output. After a
count of the last memory address, the address
counter will ’roll- over’ and the memory will continue
to output data.
Acknowledge in Read Mode. In all read modes
the ST24/25x16 wait for an acknowledge during the
9th bit time. If the master does not pull the SDA line
low during this time, the ST24/25x16 terminate the
data transfer and switches to a standby state.
13/17
ST24/25C16, ST24/25W16
ORDERING INFORMATION SCHEME
Example:
Operating Voltage
ST24C16
Range
24 4.5V to 5.5V
C Standard
25 2.5V to 5.5V
W Hardware
Write Control
M
1
TR
Package
B PSDIP8
0.25mm Frame
M SO8
150mil Width
Temperature Range
1
0 to 70 °C
6
–40 to 85 °C
Option
TR Tape & Reel
Packing
3 (1) –40 to 125 °C
Note: 1. Temperature range on special request only.
Devices are shipped from the factory with the memory content set at all "1’s" (FFh).
For a list of available options (Operating Voltage, Package, etc...) or for further information on any aspect
of this device, please contact the STMicroelectronics Sales Office nearest to you.
14/17
ST24/25C16, ST24/25W16
PSDIP8 - 8 pin Plastic Skinny DIP, 0.25mm lead frame
mm
Symb
Typ
inches
Min
Max
A
3.90
A1
Min
Max
5.90
0.154
0.232
0.49
–
0.019
–
A2
3.30
5.30
0.130
0.209
B
0.36
0.56
0.014
0.022
B1
1.15
1.65
0.045
0.065
C
0.20
0.36
0.008
0.014
D
9.20
9.90
0.362
0.390
E
7.62
–
–
6.00
6.70
–
–
eA
7.80
eB
Typ
–
–
0.236
0.264
–
–
–
0.307
–
–
10.00
–
0.394
L
3.00
3.80
0.118
0.150
N
8
E1
e1
2.54
0.100
8
A2
A1
B
0.300
A
L
e1
eA
eB
B1
D
C
N
E1
E
1
PSDIP-a
Drawing is not to scale.
15/17
ST24/25C16, ST24/25W16
SO8 - 8 lead Plastic Small Outline, 150 mils body width
mm
Symb
Typ
inches
Min
Max
A
1.35
A1
Min
Max
1.75
0.053
0.069
0.10
0.25
0.004
0.010
B
0.33
0.51
0.013
0.020
C
0.19
0.25
0.007
0.010
D
4.80
5.00
0.189
0.197
E
3.80
4.00
0.150
0.157
–
–
–
–
H
5.80
6.20
0.228
0.244
h
0.25
0.50
0.010
0.020
L
0.40
0.90
0.016
0.035
α
0°
8°
0°
8°
N
8
e
1.27
Typ
0.050
8
CP
0.10
0.004
h x 45˚
A
C
B
CP
e
D
N
E
H
1
A1
SO-a
Drawing is not to scale.
16/17
α
L
ST24/25C16, ST24/25W16
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted
by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to
change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not
authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
The ST logo is a registered trademark of STMicroelectronics
© 1999 STMicroelectronics - All Rights Reserved
All other names are the property of their respective owners
Purchase of I2C Components by STMicroelectronics, conveys a license under the Philips
I2C Patent. Rights to use these components in an I2C system, is granted provided that the system conforms to
the I2C Standard Specifications as defined by Philips.
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17/17