Rev.5.2_00
2-WIRE CMOS SERIAL E2PROM S-24CS16A
Seiko Instruments Inc. 1
The S-24CS16A is a 2-wired, low power and wide range
operation 16 K-bit E2PROM organized as 2048 words × 8
bits.
Page write and sequential read are available.
Features
• Low power consumption Standby: 5.0 µA Max. (VCC = 5.5 V)
Read: 0.8 mA Max. (VCC = 5.5 V)
• Operating voltage range Read: 1.8 to 5.5 V
Write: 2.7 to 5.5 V
• Page write: 16 bytes / page
• Sequential read
• Operating frequency: 400 kHz (VCC = 2.7 to 5.5 V)
• Write disable function when power supply voltage is low
• Endurance: 106 cycles / word*1 (at +25°C) write capable,
105 cycles / word*1 (at +85°C)
*1. For each address (Word: 8 bits)
• Data retention: 10 years (after rewriting 105 cycles / word at +85°C)
• Write protection: 100%
• Lead-free products
Packages
Drawing code
Package name Package Tape Reel Land
8-Pin DIP DP008-F − − −
8-Pin SOP(JEDEC) FJ008-A FJ008-D FJ008-D −
8-Pin TSSOP FT008-A FT008-E FT008-E −
WLP Please contact our sales office regarding the product with WLP package.
SNT-8A PH008-A PH008-A PH008-A PH008-A
Caution This product is intended to use in general electronic devices such as consumer electronics, office
equipment, and communications devices. Before using the product in medical equipment or
automobile equipment including car audio, keyless entry and engine control unit, contact to SII is
indispensable.
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
2
Pin Configurations
8-Pin DIP
Top view
Table 1
Pin No. Symbol Description
1 NC*1 No connection
2 NC*1 No connection
3 A2*2 TEST pin
4 GND Ground
5 SDA Serial data input / output
6 SCL Serial clock input
7 WP
Write protection input
Connected to VCC: Protection valid
Connected to GND: Protection invalid
8 VCC Power supply
*1. Connect to GND or VCC.
*2. Connect to GND.
1
2
3
4
8
7
6
5
VCC
WP
SCL
SDA
NC
NC
GND
A2
Figure 1
S-24CS16A0I-D8S1G
Remark See Dimensions for details of the package drawings.
8-Pin SOP(JEDEC)
Top view
Table 2
Pin No. Symbol Description
1 NC*1 No connection
2 NC*1 No connection
3 A2*2 TEST pin
4 GND Ground
5 SDA Serial data input / output
6 SCL Serial clock input
7 WP
Write protection input
Connected to VCC: Protection valid
Connected to GND: Protection invalid
8 VCC Power supply
*1. Connect to GND or VCC.
*2. Connect to GND.
1
2
3
4
8
7
6
5
VCC
WP
SCL
SDA
NC
NC
GND
A2
Figure 2
S-24CS16A0I-J8T1G
Remark See Dimensions for details of the package drawings.
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 3
8-Pin TSSOP
Top view
Table 3
Pin No. Symbol Description
1 NC*1 No connection
2 NC*1 No connection
3 A2*2 TEST pin
4 GND Ground
5 SDA Serial data input / output
6 SCL Serial clock input
7 WP
Write protection input
Connected to VCC: Protection valid
Connected to GND: Protection invalid
8 VCC Power supply
*1. Connect to GND or VCC.
*2. Connect to GND.
1
2
3
4
8
7
6
5
VCC
WP
SCL
SDA
NC
NC
GND
A2
Figure 3
S-24CS16A0I-T8T1G
Remark See Dimensions for details of the package drawings.
WLP
Bottom view
Table 4
Pin No. Symbol Description
1 A2*1 TEST pin
2 VCC Power supply
3 WP
Write protection input
Connected to VCC: Protection valid
Connected to GND: Protection invalid
4 SCL Serial clock input
5 SDA Serial data input / output
6 GND Ground
*1. Connect to GND.
VCC WP
SCL
SDA
GND
1
5
2 3
4
6
A2
Figure 4
S-24CS16A0I-H6Tx
Remark Please contact our sales office regarding the product with WLP package.
SNT-8A
Top view
Table 5
Pin No. Symbol Description
1 A2*1 TEST pin
2 GND Ground
3 SDA Serial data input / output
4 SCL Serial clock input
5 WP
Write protection input
Connected to VCC: Protection valid
Connected to GND: Protection invalid
6 VCC Power supply
7 NC*2 No connection
8 NC*2 No connection
*1. Connect to GND.
*2. Connect to GND or VCC.
1
2
3
4
8
7
6
5
NC
NC
VCC
WP
A2
GND
SDA
SCL
Figure 5
S-24CS16A0I-I8T1G
Remark See Dimensions for details of the package drawings.
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
4
Block Diagram
VCC
GND
SCL
SDA
DIN
DOUT
R/W
LOAD INC
COMP
LOAD
WP
Start / Stop
Detector
Serial Clock
Controller High-Voltage Generator
Voltage Detector
Device Address
Comparator
Address
Counter
Y Decoder
Data Register
E2PROM
X Decoder
Selector
Data Output
ACK Output
Controller
Figure 6
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 5
Absolute Maximum Ratings
Table 6
Item Symbol Absolute Maximum Rating Unit
Power supply voltage VCC −0.3 to +7.0 V
Input voltage VIN −0.3 to + 7.0 V
Output voltage VOUT −0.3 to + 7.0 V
Operating ambient temperature Topr −40 to +85 °C
Storage temperature Tstg −65 to +150 °C
Caution The absolute maximum ratings are rated values exceeding which the product could suffer
physical damage. These values must therefore not be exceeded under any conditions.
Recommended Operating Conditions
Table 7
Item Symbol Condition Min. Typ. Max. Unit
Read Operation 1.8 − 5.5 V
Power supply voltage VCC Write Operation 2.7 − 5.5 V
VCC = 2.7 to 5.5 V 0.7 × VCC − V
CC V
High level input voltage VIH VCC = 1.8 to 2.7 V 0.8 × VCC − V
CC V
VCC = 2.7 to 5.5 V 0.0 − 0.3 × VCC V
Low level input voltage VIL VCC = 1.8 to 2.7 V 0.0 − 0.2 × VCC V
Pin Capacitance
Table 8
(Ta = 25°C, f = 1.0 MHz, VCC = 5 V)
Item Symbol Condition Min. Typ. Max. Unit
Input capacitance CIN VIN = 0 V (SCL, A2, WP) − − 10 pF
Input / output capacitance CI / O VI / O = 0 V (SDA) − − 10 pF
Endurance
Table 9
Item Symbol Operation temperature Min. Typ. Max. Unit
Endurance NW −40 to +85°C 105 − − cycles / word*1
*1. For each address (Word: 8 bits)
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
6
DC Electrical Characteristics
Table 10
VCC = 4.5 to 5.5 V
f = 400 kHz
VCC = 2.7 to 4.5 V
f = 100 kHz
VCC = 1.8 to 2.7 V
f = 100 kHz
Item Symbol Condition
Min. Typ. Max. Min. Typ. Max. Min. Typ. Max.
Unit
Current consumption
(READ) ICC1 − − − 0.8 − − 0.5 − − 0.3 mA
Current consumption
(WRITE) ICC2 − − − 4.0 − − 3.0 − − − mA
Table 11
Item Symbol Condition
VCC = 4.5 to 5.5 V VCC = 2.7 to 4.5 V VCC = 1.8 to 2.7 V Unit
Min. Typ. Max. Min. Typ. Max. Min. Typ. Max.
Standby current
consumption ISB V
IN = VCC or GND − − 5.0 − − 3.0 − − 3.0 µA
Input leakage
current ILI V
IN = GND to VCC − 0.1 1.0 − 0.1 1.0 − 0.1 1.0 µA
Output leakage
current ILO V
OUT = GND to VCC − 0.1 1.0 − 0.1 1.0 − 0.1 1.0 µA
IOL = 3.2 mA − − 0.4 − − − − − − V Low level output
voltage VOL IOL = 1.5 mA − − 0.3 − − 0.3 − − 0.3 V
Current address
hold voltage VAH − 1.5 − 5.5 1.5 − 4.5 1.5 − 2.7 V
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 7
AC Electrical Characteristics
Table 12 Measurement Conditions
Input pulse voltage 0.1 × VCC to 0.9 × VCC
Input pulse rising / falling time 20 ns
Output judgement voltage 0.5 × VCC
Output load 100 pF + Pull-up resistor 1.0 kΩ
SDA
C = 100 pF
VCC
R = 1.0 kΩ
Figure 7 Output Load Circuit
Table 13
VCC = 4.5 to 5.5 V VCC = 2.7 to 4.5 V VCC = 1.8 to 2.7 V
Item Symbol
Min. Typ. Max. Min. Typ. Max. Min. Typ. Max. Unit
SCL clock frequency fSCL 0 − 400 0 − 400 0 − 100 kHz
SCL clock time “L” tLOW 1.0 − − 1.0 − − 4.7 − − µs
SCL clock time ”H” tHIGH 0.9 − − 0.9 − − 4.0 − − µs
SDA output delay time tAA 0.1 − 0.9 0.1 − 0.9 0.1 − 3.5 µs
SDA output hold time tDH 50 − − 50 − − 100 − − ns
Start condition setup time tSU.STA 0.6 − − 0.6 − − 4.7 − − µs
Start condition hold time tHD.STA 0.6 − − 0.6 − − 4.0 − − µs
Data input setup time tSU.DAT 100 − − 100 − − 200 − − ns
Data input hold time tHD.DAT 0 − − 0 − − 0 − − ns
Stop condition setup time tSU.STO 0.6 − − 0.6 − − 4.0 − − µs
SCL, SDA rising time tR − − 0.3 − − 0.3 − − 1.0 µs
SCL, SDA falling time tF − − 0.3 − − 0.3 − − 0.3 µs
Bus release time tBUF 1.3 − − 1.3 − − 4.7 − − µs
Noise suppression time tI − − 50 − − 100 − − 100 ns
SCL
SDA IN
SDA OUT
tBUF
tR
tSU.STO
tSU.DAT
tHD.DAT
tDH
tAA
tHIGH tLOW
tHD.STA
tSU.STA
tF
Figure 8 Bus Timing
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
8
Table 14
VCC = 2.7 to 5.5 V
Item Symbol
Min. Typ. Max.
Unit
Write time tWR − 4.0 10.0 ms
SCL
SDA
Write data
Acknowledge
Stop Condition Start Condition
D0
tWR
Figure 9 Write Cycle Timing
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 9
Pin Functions
1. A2 (TEST) Pin
The slave address cannot be assigned in the S-24CS16A since the addressing function is removed.
The A2 pin should be connected to the GND.
2. SDA (Serial Data Input / Output) Pin
The SDA pin is used for bi-directional transmission of serial data. It consists of a signal input pin and an Nch open-
drain output pin.
The SDA line is usually pulled up to the VCC, and OR-wired with other open-drain or open-collector output devices.
3. SCL (Serial Clock Input) Pin
The SCL pin is used for serial clock input. Since signals are processed at the rising or falling edge of the SCL clock
input signal, attention should be paid to the rising time and falling time to conform to the specifications.
4. WP (Write Protection Input) Pin
The write protection is enabled by connecting the WP pin to the VCC. When there is no need for write protection,
connect the pin to the GND.
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
10
Operation
1. Start Condition
Start is identified by a high to low transition of the SDA line while the SCL line is stable at high.
Every operation begins from a start condition.
2. Stop Condition
Stop is identified by a low to high transition of the SDA line while the SCL line is stable at high.
When a device receives a stop condition during a read sequence, the read operation is interrupted, and the device
enters standby mode.
When a device receives a stop condition during a write sequence, the reception of the write data is halted, and the
E2PROM initiates a write cycle.
tSU.STA tHD.STA tSU.STO
Start Condition Stop Condition
SCL
SDA
Figure 10 Start / Stop Conditions
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 11
3. Data Transmission
Changing the SDA line while the SCL line is low, data is transmitted.
Changing the SDA line while the SCL line is high, a start or stop condition is recognized.
tSU.DAT tHD.DAT
SCL
SDA
Figure 11 Data Transmission Timing
4. Acknowledge
The unit of data transmission is 8 bits. During the 9th clock cycle period the receiver on the bus pulls down the SDA
line to acknowledge the receipt of the 8-bit data.
When an internal write cycle is in progress, the device does not generate an acknowledge.
1 8 9
Acknowledge
Output
tAA tDH
Start Condition
SCL
(E2PROM Input)
SDA
(Master Output)
SDA
(E2PROM Output)
Figure 12 Acknowledge Output Timing
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
12
5. Device Addressing
To start communication, the master device on the system generates a start condition to the bus line. Next, the master
device sends 7-bit device address and a 1-bit read / write instruction code on to the SDA bus.
The 4 most significant bits of the device address are called the “Device Code”, and are fixed to “1010”.
The successive 3 bits (P2, P1 and P0) are used to define a page address and choose the eight 256-byte memory
blocks.
Page Address
1 0 1 0 P2 P1 P0 R / W
Device Code
MSB LSB
Figure 13 Device Address
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 13
6. Write
6. 1 Byte Write
When the master sends a 7-bit device address and a 1-bit read / write instruction code set to “0”, following a start
condition, the E2PROM acknowledges it. The E2PROM then receives an 8-bit word address and responds with an
acknowledge. After the E2PROM receives 8-bit write data and responds with an acknowledge, it receives a stop
condition and that initiates the write cycle at the addressed memory.
During the write cycle all operations are forbidden and no acknowledge is generated.
P2 P1
P0
S
T
A
R
T
1 0 1 0
W
R
I
T
E
DEVICE
ADDRESS
R
/
W
M
S
B
SDA LINE
ADR INC
(ADDRESS INCREMENT)
A
C
K
L
S
B
WORD ADDRESS
A
C
K
0
S
T
O
P
DATA
W7 W6 W5 W4 W3 W2 W1 W0 D7 D6 D5 D4 D3
D2
D1
D0
A
C
K
A
C
K
Figure 14 Byte Write
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
14
6. 2 Page Write
The page write mode allows up to 16 bytes to be written in a single write operation in the S-24CS16A.
Basic data transmission procedure is the same as that in the “Byte Write”. But instead of generating a stop
condition, the master transmitts 8-bit write data up to 8 bytes before the page write.
When the E2PROM receives a 7-bit device address and a 1-bit read / write instruction code set to “0”, following a
start condition, it generates an acknowledge. Then the E2PROM receives an 8-bit word address, and responds with
an acknowledge. After the E2PROM receives 8-bit write data and responds with an acknowledge, it receives 8-bit
write data corresponding to the next word address, and generates an acknowledge. The E2PROM repeats
reception of 8-bit write data and generation of acknowledge in succession. The E2PROM can receive as many write
data as the maximum page size.
Receiving a stop condition initiates a write cycle of the area starting from the designated memory address and
having the page size equal to the received write data.
R
/
W
S
T
A
R
T
1
0
1
0
W
R
I
T
E
S
T
O
P
DEVICE
ADDRESS DATA (n)
WORD ADDRESS (n)
M
S
B
SDA
LINE
P2
P1
P0
A
C
K
L
S
B
A
C
K
A
C
K
0
W7
W6
W5
W4
W3
W2
W1W0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D0
D7
D0
ADR INC
A
C
K
ADR INC
A
C
K
DATA (n+1) DATA (n+x)
ADR INC
Figure 15 Page Write
In S-24CS16A, the lower 4 bits of the word address are automatically incremented every time when the E2PROM
receives 8-bit write data. If the size of the write data exceeds 16 bytes, the upper 4 bits of the word address and
page address (P2, P1 and P0) remain unchanged, and the lower 4 bits are rolled over and previously received data
will be overwritten.
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 15
6. 3 Write Protection
Write protection is available in the S-24CS16A. When the WP pin is connected to the VCC, write operation to
memory area is forbidden at all.
When the WP pin is connected to the GND, the write protection is invalid, and write operation in all memory area is
available.
Fix the level of the WP pin from the rising edge of SCL for loading the last write data (D0) until the end of the write
time (10 ms max.). If the WP pin changes during this time, the address data being written at this time is not
guaranteed.
There is no need for using write protection, the WP pin should be connected to the GND. The write protection is
valid in the operating voltage range.
SDA
WP
SCL
Acknowledge
WP Pin Fixed Period
Stop
Condition
Start
Condition
Write Data
t
WR
D0
Figure 16 WP Pin Fixed Period
6. 4 Acknowledge Polling
Acknowledge polling is used to know the completion of the write cycle in the E2PROM.
After the E2PROM receives a stop condition and once starts the write cycle, all operations are forbidden and no
response is made to the signal transmitted by the master device.
Accordingly the master device can recognize the completion of the write cycle in the E2PROM by detecting a
response from the slave device after transmitting the start condition, the device address and the read / write
instruction code to the E2PROM, namely to the slave devices.
That is, if the E2PROM does not generate an acknowledge, the write cycle is in progress and if the E2PROM
generates an acknowledge, the write cycle has been completed.
Keep the level of the WP pin fixed until acknowledge is confirmed.
It is recommended to use the read instruction “1” as the read / write instruction code transmitted by the master
device.
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
16
7. Read
7. 1 Current Address Read
Either in writing or in reading the E2PROM holds the last accessed memory address, internally incremented by one.
The memory address is maintained as long as the power voltage is higher than the current address hold voltage
VAH.
The master device can read the data at the memory address of the current address pointer without assigning the
word address as a result, when it recognizes the position of the address pointer in the E2PROM. This is called
“Current Address Read”.
In the following the address counter in the E2PROM is assumed to be “n”.
When the E2PROM receives a 7-bit device address and a 1-bit read / write instruction code set to “1” following a
start condition, it responds with an acknowledge. However, the page address (P2, P1 and P0) become invalid and
the memory address of the current address pointer becomes valid.
Next an 8-bit data at the address “n” is sent from the E2PROM synchronous to the SCL clock. The address counter
is incremented at the falling edge of the SCL clock for the 8th bit data, and the content of the address counter
becomes n+1.
The master device outputs stop condition not an acknowledge, the reading of E2PROM is ended.
S
T
A
R
T
R
E
A
D
S
T
O
P
DEVICE
ADDRESS
R
/
W
M
S
B
SDA LINE P2 P1 P0 D7 D6 D5 D4 D3 D2 D1 D0
A
C
K
L
S
B
1
DATA
NO ACK from
Master Device
0
ADR INC
1 0 1
Figure 17 Current Address Read
Attention should be paid to the following point on the recognition of the address pointer in the E2PROM.
In the read operation the memory address counter in the E2PROM is automatically incremented at every falling
edge of the SCL clock for the 8th bit of the output data. In the write operation, on the other hand, the upper bits of
the memory address (the upper bits of the word address and page address)*1 are left unchanged and are not
incremented at the falling edge of the SCL clock for the 8th bit of the received data.
*1. The upper 4 bits of the word address and the page address P2, P1 and P0.
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 17
7. 2 Random Read
Random read is used to read the data at an arbitrary memory address.
A dummy write is performed to load the memory address into the address counter.
When the E2PROM receives a 7-bit device address and a 1-bit read / write instruction code set to “0” following a
start condition, it responds with an acknowledge. The E2PROM then receives an 8-bit word address and responds
with an acknowledge. The memory address is loaded to the address counter in the E2PROM by these operations.
Reception of write data does not follow in a dummy write whereas reception of write data follows in a byte write and
in a page write.
Since the memory address is loaded into the memory address counter by dummy write, the master device can read
the data starting from the arbitrary memory address by transmitting a new start condition and performing the same
operation in the current address read.
That is, when the E2PROM receives a 7-bit device address and a 1-bit read / write instruction code set to “1”,
following a start condition signal, it responds with an acknowledge. Next, 8-bit data is transmitted from the
E2PROM in synchronous to the SCL clock. The master device outputs stop condition not an acknowledge, the
reading of E2PROM is ended.
SDA
LINE
S
T
A
R
T
1 0 1 0
W
R
I
T
E
DEVICE
ADDRESS WORD ADDRESS (n)
R
/
W
M
S
B
P2 P1 P0
A
C
K
L
S
B
W7
W6
W5
W4 W3 W2 W1 W0
A
C
K
0
DUMMY WRITE
S
T
O
P
S
T
A
R
T
1 0 1 0
R
E
A
D
DEVICE
ADDRESS
R
/
W
M
S
B
P2 P1 P0
A
C
K
L
S
B
1
NO ACK from
Master Device
ADR INC
DATA
D7 D6
D5
D4
D3
D2
D1 D0
Figure 18 Random Read
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
18
7. 3 Sequential Read
When the E2PROM receives a 7-bit device address and a 1-bit read / write instruction code set to “1” following a
start condition both in current and random read operations, it responds with an acknowledge.
An 8-bit data is then sent from the E2PROM synchronous to the SCL clock and the address counter is automatically
incremented at the falling edge of the SCL clock for the 8th bit data.
When the master device responds with an acknowledge, the data at the next memory address is transmitted.
Response with an acknowledge by the master device has the memory address counter in the E2PROM
incremented and makes it possible to read data in succession. This is called “Sequential Read”.
The master device outputs stop condition not an acknowledge, the reading of E2PROM is ended.
Data can be read in succession in the sequential read mode. When the memory address counter reaches the last
word address, it rolls over to the first memory address.
R
E
A
D
S
T
O
P
DEVICE
ADDRESS
R
/
W
ADR INC
A
C
K
A
C
K
A
C
K
1
ADR INC
A
C
K
ADR INC
SDA
LINE
DATA (n)
D7
D0
D7
D0
D7
D0 D7 D0
DATA (n+1) DATA (n+2) DATA (n+x)
NO ACK from
Master Device
ADR INC
Figure 19 Sequential Read
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 19
8. Address Increment Timing
The timing for the automatic address increment is the falling edge of the SCL clock for the 8th bit of the read data in
read operation and the falling edge of the SCL clock for the 8th bit of the received data in write operation.
SCL
SDA R / W = 1
Address Increment
8 9 1 8 9
D7 Output
D0 Output
ACK Output
Figure 20 Address Increment Timing in Reading
R / W = 0
Address Increment
8 9 189
D7 Input D0 Input ACK Output
SCL
SDA
ACK Output
Figure 21 Address Increment Timing in Writing
Write Inhibition Function at Low Power Voltage
The S-24CS16A has a detection circuit for low power voltage. The detection circuit cancels a write instruction when the
power voltage is low or the power switch is on. The detection voltage is 1.85 V typically and the release voltage is 1.95
V typically, the hysteresis of approximate 0.1 V thus exists. (See Figure 22.)
When a low power voltage is detected, a write instruction is canceled at the reception of a stop condition.
When the power voltage lowers during a data transmission or a write operation, the data at the address of the operation
is not assured.
Release voltage (+VDET)
1.95 V Typ.
Power supply voltage
Hysteresis width
0.1 V approximately
Detection voltage (−VDET)
1.85 V Typ.
Write Instruction cancel
Figure 22 Operation at Low Power Voltage
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
20
Using S-24CS16A
1. Adding a pull-up resistor to SDA I/O pin and SCL input pin
Add a 1 to 5 kΩ pull-up resistor to the SCL input pin*1 and the SDA I/O pin in order to enable the functions of the I2C -
bus protocol. Normal communication cannot be provided without a pull-up resistor.
*1. When the SCL input pin of the E2PROM is connected to a tri-state output pin of the microprocessor, connect the
same pull-up resistor to prevent a high impedance status from being input to the SCL input pin.
This protects the E2PROM from malfunction due to an undefined output (high impedance) from the tri-state pin
when the microprocessor is reset when the voltage drops.
2. I/O pin equivalent circuit
The I/O pins of this IC do not include pull-up and pull-down resistors. The SDA pin is an open-drain output. The following
shows the equivalent circuits.
SCL
Figure 23 SCL Pin
SDA
Figure 24 SDA Pin
WP
Figure 25 WP Pin
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 21
3. Matching phases while E2PROM is accessed
The S-24CS16A does not have a pin for resetting (the internal circuit), therefore, the E2PROM cannot be forcibly reset
externally. If a communication interruption occurs in the E2PROM, it must be reset by software.
For example, even if a reset signal is input to the microprocessor, the internal circuit of the E2PROM is not reset as
long as the stop condition is not input to the E2PROM. In other words, the E2PROM retains the same status and
cannot shift to the next operation. This symptom applies to the case when only the microprocessor is reset when the
power supply voltage drops. With this status, if the power supply voltage is restored, reset the E2PROM (after
matching the phase with the microprocessor) and input an instruction. The following shows this reset method.
[How to reset E2PROM]
The E2PROM can be reset by the start and stop instructions. When the E2PROM is reading data “0” or is
outputting the acknowledge signal, 0 is output to the SDA line. In this status, the microprocessor cannot output an
instruction to the SDA line. In this case, terminate the acknowledge output operation or read operation, and then
input a start instruction. Figure 26 shows this procedure.
First, input the start condition. Then transmit 9 clocks (dummy clocks) of SCL. During this time, the
microprocessor sets the SDA line to high level. By this operation, the E2PROM interrupts the acknowledge output
operation or data output, so input the start condition*1. When a start condition is input, the E2PROM is reset. To
make doubly sure, input the stop condition to the E2PROM. Normal operation is then possible.
1 2 8 9
SCL
SDA
Start
condition
Start
condition
Dummy clock
Stop
condition
Figure 26 Resetting E2PROM
*1. After 9 clocks (dummy clocks), if the SCL clock continues to be output without a start condition being input, a
write operation may be started upon receipt of a stop condition. To prevent this, input a start condition after 9
clocks (dummy clocks).
Remark It is recommended to perform the above reset using dummy clocks when the system is initialized after
the power supply voltage has been raised.
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
22
4. Acknowledge check
The I2C-bus protocol includes an acknowledge check function as a handshake function to prevent a communication
error. This function allows detection of a communication failure during data communication between the
microprocessor and E2PROM. This function is effective to prevent malfunction, so it is recommended to perform an
acknowledge check on the microprocessor side.
5. Built-in power-on-clear circuit
E2PROMs have a built-in power-on-clear circuit that initializes the E2PROM. Unsuccessful initialization may cause a
malfunction. For the power-on-clear circuit to operate normally, the following conditions must be satisfied for raising
the power supply voltage.
5. 1 Raising power supply voltage
Raise the power supply voltage, starting at 0.2 V maximum, so that the voltage reaches the power supply voltage to
be used within the time defined by tRISE as shown in Figure 27.
For example, when the power supply voltage to be used is 5.0 V, tRISE is 200 ms as shown in Figure 28. The power
supply voltage must be raised within 200 ms.
0.2 V
V
INIT
(Max.)
t
INIT*2
(Max.)
t
RISE
(Max.)
Power supply voltage
(V
CC
)
0 V
*1
*1. 0 V means there is no difference in potential between the VCC pin and the GND pin of the E2PROM.
*2. tINIT is the time required to initialize the E2PROM. No instructions are accepted during this time.
Figure 27 Raising Power Supply Voltage
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 23
Rise time (t
RISE
) Max.
[ms]
Power supply voltage (V
CC
)
[V]
50
5.0
4.0
3.0
2.0
100 150 200
For example: If your E2PROM supply voltage = 5.0 V, raise the power supply voltage to 5.0 V within 200 ms.
Figure 28 Raising Time of Power Supply Voltage
When initialization is successfully completed via the power-on-clear circuit, the E2PROM enters the standby status.
If the power-on-clear circuit does not operate, the following are the possible causes.
(1) Because the E2PROM has not been initialized, an instruction formerly input is valid or an instruction may be
inappropriately recognized. In this case, writing may be performed.
(2) The voltage may have dropped due to power off while the E2PROM is being accessed. Even if the microprocessor
is reset due to the low power voltage, the E2PROM may malfunction unless the power-on-clear operation conditions
of E2PROM are satisfied. For the power-on-clear operation conditions of E2PROM, refer to 5.1 Raising power
supply voltage.
If the power-on-clear circuit does not operate, match the phase (reset) so that the internal E2PROM circuit is normally
reset. The statuses of the E2PROM immediately after the power-on-clear circuit operates and when phase is matched
(reset) are the same.
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
24
5. 2 Wait for the initialization sequence to end
The E2PROM executes initialization during the time that the supply voltage is increasing to its normal value. All
instructions must wait until after initialization. The relationship between the initialization time (tINIT) and rise time
(tRISE) is shown in Figure 29.
Rise time (t
RISE
)
[s]
E
2
PROM
initialization time
(t
INIT
) Max.
[s]
100 m
10 m
1.0 m
100 µ
10 µ
1.0 µ
1.0 µ 10 µ 100 µ 1.0 m 10 m 100 m
Figure 29 Initialization Time of E2PROM
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 25
6. Data hold time (tHD.DAT = 0 ns)
If SCL and SDA of the E2PROM are changed at the same time, it is necessary to prevent the start / stop condition from
being mistakenly recognized due to the effect of noise. If a start/stop condition is mistakenly recognized during
communication, the E2PROM enters the standby status.
It is recommended that SDA is delayed from the falling edge of SCL by 0.3 µs minimum in the S-24CS16A. This is to
prevent time lag caused by the load of the bus line from generating the stop (or start) condition.
SCL
SDA
t
HD.DAT
= 0.3 µs Min.
Figure 30 E2PROM Data Hold Time
7. SDA pin and SCL pin noise suppression time
The S-24CS16A includes a built-in low-pass filter to suppress noise at the SDA and SCL pins. This means that if the
power supply voltage is 5.0 V, noise with a pulse width of 160 ns or less can be suppressed.
The guaranteed for details, refer to noise suppression time (tI) in Table 13.
200
100
300
2 3 4 5
Noise suppression time (t
I
) Max.
[ns]
Power supply voltage (V
CC
)
[V]
Figure 31 Noise Suppression Time for SDA and SCL Pins
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
26
8. Trap: E2PROM operation in case that the stop condition is received during write operation before
receiving the defined data value (less than 8-bit) to SCL pin
When the E2PROM receives the stop condition signal compulsorily, during receiving 1 byte of write data, “write”
operation is aborted.
When the E2PROM receives the stop condition signal after receiving 1 byte or more of data for “page write”, 8-bit of
data received normally before receiving the stop condition signal can be written.
9. Trap: E2PROM operation and write data in case that write data is input more than defined page size at
“page write”
When write data is input more than defined page size at page write operation, for example, S-24CS16A (which can be
executed 16-byte page write) is received data more than 17 byte, 8-bit data of the 17th byte is over written to the first
byte in the same page. Data over the capacity of page address cannot be written.
10. Trap: Severe environments
Absolute maximum ratings: Do not operate these ICs in excess of the absolute maximum ratings (as listed on the data
sheet). Exceeding the supply voltage rating can cause latch-up.
Operations with moisture on the E2PROM pins may occur malfunction by short-circuit between pins. Especially, in
occasions like picking the E2PROM up from low temperature tank during the evaluation. Be sure that not remain frost
on E2PROM pin to prevent malfunction by short-circuit.
Also attention should be paid in using on environment, which is easy to dew for the same reason.
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 27
Precautions
● Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in electrostatic
protection circuit.
● SII claims no responsibility for any and all disputes arising out of or in connection with any infringement of the
products including this IC upon patents owned by a third party.
Precautions for WLP package
● The side of device silicon substrate is exposed to the marking side of device package. Since this portion has lower
strength against the mechanical stress than the standard plastic package, chip, crack, etc should be careful of the
handing of a package enough. Moreover, the exposed side of silicon has electrical potential of device substrate, and
needs to be kept out of contact with the external potential.
● In this package, the overcoat of the resin of translucence is carried out on the side of device area. Keep it mind that it
may affect the characteristic of a device when exposed a device in the bottom of a high light source.
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
28
Characteristics (Typical Data)
1. DC Characteristics
1. 1 Current consumption (READ) ICC1 1. 2 Current consumption (READ) ICC1
vs. Ambient temperature Ta vs. Ambient temperature Ta
VCC = 5.5 V
fSCL = 100 kHz
DATA =0101
–40 0 85
300
100
200
0
ICC1
(µA)
Ta (°C)
Ta (°C)
VCC =3.3 V
fSCL = 100 kHz
DATA = 0101
–40 0 85
300
100
200
0
ICC1
(µA)
1. 3 Current consumption (READ) ICC1 1. 4 Current consumption (READ) ICC1
vs. Ambient temperature Ta vs. Power supply voltage VCC
VCC = 1.8 V
fSCL = 100 kHz
DATA = 0101
300
100
200
0
ICC1
(µA)
Ta (°C)
–40 0 85
Ta =25 °C
fSCL = 100 kHz
DATA = 0101
2 3 4 5 6 7
VCC (V)
300
100
200
0
ICC1
(µA)
1. 5 Current consumption (READ) ICC1 1. 6 Current consumption (READ) ICC1
vs. Power supply voltage VCC vs. Clock frequency fSCL
Ta = 25 °C
fSCL = 400 kHz
DATA = 0101
2 3 4 5 6 7
VCC (V)
500
400
300
200
100
0
ICC1
(µA)
VCC = 5.0 V
Ta = 25 °C
100k
fSCL (Hz)
400k 1M
500
400
300
200
100
0
ICC1
(µA)
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 29
1. 7 Current consumption (PROGRAM) ICC2 1. 8 Current consumption (PROGRAM) ICC2
vs. Ambient temperature Ta vs. Ambient temperature Ta
VCC = 5.5 V
Ta (°C)
–40 0 85
1.0
0.5
0
ICC2
(mA)
VCC = 3.3 V
Ta (°C)
–40 0 85
1.0
0.5
0
ICC2
(mA)
1. 9 Current consumption (PROGRAM) ICC2 1. 10 Current consumption (PROGRAM) ICC2
vs. Ambient temperature Ta vs. Power supply voltage VCC
VCC = 2.7 V
1.0
0.5
0
ICC2
(mA)
Ta (°C)
–40 0 85
Ta = 25 °C
VCC (V)
1.0
0.5
0
ICC2
(mA)
2
134 5 6
1. 11 Standby current consumption ISB 1. 12 Input leakage current ILI
vs. Ambient temperature Ta vs. Ambient temperature Ta
2.0
1.0
VCC = 5.5 V
0
ISB
(µA)
Ta (°C)
–40 0 85
1.0
0.5
0
ILI
(µA)
Ta (°C)
–40 0 85
VCC = 5.5 V
SDA, SCL, WP = 0 V
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
30
1. 13 Input leakage current ILI 1. 14 Output leakage current ILO
vs. Ambient temperature Ta vs. Ambient temperature Ta
1.0
0.5
VCC = 5.5 V
0
ILI
(µA)
Ta (°C)
–40 0 85
SDA, SCL, WP
=
5.5 V
1.0
0.5
VCC = 5.5 V
SDA = 0 V
0
ILO
(µA)
Ta (°C)
–40 085
1. 15 Output leakage current ILO 1. 16 Low level output voltage VOL
vs. Ambient temperature Ta vs. Low level output current IOL
1.0
0.5
VCC = 5.5 V
SDA = 5.5 V
0
ILO
(µA)
Ta (°C)
–40 0 85
0.3
0.2
V
OL
(V)
0.1
021 3 4 5 6
Ta = –40 °C
IOL (mA)
VCC = 1.8 V
VCC = 5.0 V
1. 17 Low level output voltage VOL 1. 18 Low level output voltage VOL
vs. Low level output current IOL vs. Low level output current IOL
0.3
0.2
VOL
(V)
0.1
0
2 1 3 4 5 6
Ta = 25 °C
IOL (mA)
VCC = 1.8 V
VCC = 5.0 V
0.3
0.2
VOL
(V)
0.1
021 3 4 5 6
Ta = 85 °C
IOL (mA)
VCC = 1.8 V
VCC = 5.0 V
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 31
1. 19 High input inversion voltage VIH 1. 20 High input inversion voltage VIH
vs. Power supply voltage VCC vs. Ambient temperature Ta
Ta = 25 °C
1.0
0
2.0
3.0
V
IH
(V)
VCC (V)
7 6 2 3 4 5 1
SDA, SCL
VCC = 5.0 V
SDA, SCL
1.0
0
2.0
3.0
V
IH
(V)
Ta (°C)
–40 0 85
1. 21 Low input inversion voltage VIL 1. 22 Low input inversion voltage VIL
vs. Power supply voltage VCC vs. Ambient temperature Ta
Ta = 25 °C
SDA, SCL
1.0
0
2.0
3.0
VIL
(V)
VCC (V)
7 6 2 3 4 5
1
VCC =5.0 V
SDA, SCL
1.0
0
2.0
3.0
VIL
(V)
Ta (°C)
–40 0 85
1. 23 Low power supply detection voltage −VDET 1. 24 Low power supply release voltage +VDET
vs. Ambient temperature Ta vs. Ambient temperature Ta
1.0
0
2.0
–VDET
(V)
Ta (°C)
–40 0 85
1.0
0
2.0
+VDET
(V)
Ta (°C)
–40 0 85
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
32
2. AC Characteristics
2. 1 Maximum operating frequency fMAX. 2. 2 Write time tWR vs. Power supply voltage VCC
vs. Power supply voltage VCC
10k
2 3 4 5
Ta = 25 °C
VCC (V)
f
MAX.
(Hz)
1
100k
1M
VCC (V)
8
4
Ta = 25 °C
t
WR
(ms)
2
6
0
6 234 5 1
2. 3 Write time tWR vs. Ambient temperature Ta 2. 4 Write time tWR vs. Ambient temperature Ta
VCC = 4.5 V
tWR
(ms)
9
6
3
0
Ta (°C)
–40 0 85
VCC = 2.7 V
t
WR
(ms)
9
6
3
0
Ta (°C)
–40 0 85
2. 5 SDA output delay time tAA 2. 6 SDA output delay time tAA
vs. Ambient temperature Ta vs. Ambient temperature Ta
Ta (°C)
–40 0 85
VCC = 4.5 V
1.0
0.5
tAA
(µs)
0
Ta (°C)
–40 0 85
VCC = 2.7 V
1.0
0.5
tAA
(µs)
0
2-WIRE CMOS SERIAL E2PROM
Rev.5.2_00 S-24CS16A
Seiko Instruments Inc. 33
2. 7 SDA output delay time tAA
vs. Ambient temperature Ta
Ta (°C)
–40 0 85
VCC = 1.8 V
1.0
0.5
tAA
(µs)
0
2-WIRE CMOS SERIAL E2PROM
S-24CS16A Rev.5.200
Seiko Instruments Inc.
34
Product Name Structure
1. 8-Pin DIP, 8-Pin SOP(JEDEC), 8-Pin TSSOP, SNT-8A Packages
S-24CS16A 0I - xxxx G
Package name (abbreviation) and IC packing specifications
D8S1 : 8-Pin DIP, Tube
J8T1 : 8-Pin SOP (JEDEC), Tape
T8T1 : 8-Pin TSSOP, Tape
I8T1 : SNT-8A, Tape
Fixed
Product name
S-24CS16A: 16 Kbit
2. WLP Package
S-24CS16A 0I - H6Tx
Package name (abbreviation) and IC packing specifications
H6Tx : WLP, Tape
Fixed
Product name
S-24CS16A: 16 Kbit
Remark Please contact our sales office regarding the product with WLP package.
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
DIP8-F-PKG Dimensions
No. DP008-F-P-SD-3.0
DP008-F-P-SD-3.0
0.48±0.1
2.54
0.89 1.3
0° to 15°
0.25+0.11
-0.05
7.62
9.6(10.6max.)
14
5
8
No. FJ008-A-P-SD-2.1
No.
TITLE
SCALE
UNIT mm
SOP8J-D-PKG Dimensions
Seiko Instruments Inc.
FJ008-A-P-SD-2.1
0.4±0.05
1.27
0.20±0.05
5.02±0.2
14
85
No.
TITLE
SCALE
UNIT mm
5
8
1
4
ø2.0±0.05
ø1.55±0.05 0.3±0.05
2.1±0.1
8.0±0.1
5°max.
6.7±0.1
2.0±0.05
Seiko Instruments Inc.
Feed direction
4.0±0.1(10 pitches:40.0±0.2)
SOP8J-D-Carrier Tape
No. FJ008-D-C-SD-1.1
FJ008-D-C-SD-1.1
No.
TITLE
SCALE
UNIT mm
QTY. 2,000
2±0.5
13.5±0.5
60°
2±0.5
ø13±0.2
ø21±0.8
Seiko Instruments Inc.
Enlarged drawing in the central part
SOP8J-D-Reel
No. FJ008-D-R-SD-1.1
FJ008-D-R-SD-1.1
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
TSSOP8-E-PKG Dimensions
No. FT008-A-P-SD-1.1
FT008-A-P-SD-1.1
0.17±0.05
3.00 +0.3
-0.2
0.65
0.2±0.1
14
5
8
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
ø1.55±0.05
2.0±0.05
8.0±0.1 ø1.55 +0.1
-0.05
(4.4)
0.3±0.05
1
45
8
4.0±0.1
Feed direction
TSSOP8-E-Carrier Tape
No. FT008-E-C-SD-1.0
FT008-E-C-SD-1.0
+0.4
-0.2
6.6
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
Enlarged drawing in the central part
No. FT008-E-R-SD-1.0
2±0.5
ø13±0.5
ø21±0.8
13.4±1.0
17.5±1.0
3,000
QTY.
TSSOP8-E-Reel
FT008-E-R-SD-1.0
1.97±0.03
0.2±0.05
0.48±0.02
0.08
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
SNT-8A-A-PKG Dimensions
PH008-A-P-SD-2.0
No. PH008-A-P-SD-2.0
0.5
+0.05
-0.02
123 4
56
78
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
PH008-A-C-SD-1.0
SNT-8A-A-Carrier Tape
No. PH008-A-C-SD-1.0
Feed direction
4.0±0.1
2.0±0.05
4.0±0.1
ø1.5 +0.1
-0
ø0.5±0.1
2.25±0.05
0.65±0.05
0.25±0.05
2134
7865
5°
12.5max.
9.0±0.3
ø13±0.2
(60°) (60°)
Enlarged drawing in the central part
QTY.
PH008-A-R-SD-1.0
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
SNT-8A-A-Reel
No. PH008-A-R-SD-1.0
5,000
No.
TITLE
SCALE
UNIT mm
SNT-8A-A-Land Recommendation
Seiko Instruments Inc.
PH008-A-L-SD-3.0
0.3
0.20.3
0.20.3
0.52
2.01
0.52
No. PH008-A-L-SD-3.0
0.3 0.2
Caution Making the wire pattern under the package is possible. However, note that the package
may be upraised due to the thickness made by the silk screen printing and of a solder
resist on the pattern because this package does not have the standoff.
•
The information described herein is subject to change without notice.
• Seiko Instruments Inc. is not responsible for any problems caused by circuits or diagrams described herein
whose related industrial properties, patents, or other rights belong to third parties. The application circuit
examples explain typical applications of the products, and do not guarantee the success of any specific
mass-production design.
• When the products described herein are regulated products subject to the Wassenaar Arrangement or other
agreements, they may not be exported without authorization from the appropriate governmental authority.
• Use of the information described herein for other purposes and/or reproduction or copying without the
express permission of Seiko Instruments Inc. is strictly prohibited.
• The products described herein cannot be used as part of any device or equipment affecting the human
body, such as exercise equipment, medical equipment, security systems, gas equipment, or any apparatus
installed in airplanes and other vehicles, without prior written permission of Seiko Instruments Inc.
• Although Seiko Instruments Inc. exerts the greatest possible effort to ensure high quality and reliability, the
failure or malfunction of semiconductor products may occur. The user of these products should therefore
give thorough consideration to safety design, including redundancy, fire-prevention measures, and
malfunction prevention, to prevent any accidents, fires, or community damage that may ensue.
