S-25A128B
www.sii-ic.com
125°C OPERATION
SPI SERIAL E2PROM FOR AUTOMOTIVE
© Seiko Instruments Inc., 2011 Rev.1.1_00
Seiko Instruments Inc. 1
This IC is a SPI serial E2PROM which operates under the high temperature, at high speed, with the wide range operation for
automotive components. This IC has the capacity of 128 K-bit and the organization of 16384 words × 8-bit. Page write and
Sequential read are available.
Caution Before using the product in automobile control unit or medical equipment, contact to SII is indispensable.
Features
• Operating voltage range
Read: 2.5 V ~ 5.5 V
Write: 2.5 V ~ 5.5 V
• Operation frequency: 6.5 MHz max.
• Write time: 5.0 ms max.
• SPI mode (0, 0) and (1, 1)
• Page write: 64 bytes / page
• Sequential read
• Write protect: Software, Hardware
Protect area: 25%, 50%, 100%
• Monitoring of a write memory state by the status register
• Function to prevent malfunction by monitoring clock pulse
• Write protect function during the low power supply voltage
• CMOS schmitt input (CS, SCK, SI, WP , HOLD)
• Endurance*1: 106 cycle / word*2 (Ta = +25°C)
3 × 105 cycle / word *2 (Ta = +125°C)
• Data retention: 100 years (Ta = +25°C)
50 years (Ta = +125°C)
• Memory capacity: 128 K-bit
• Initial shipment data: FFh, SRWD = 0, BP1 = 0, BP0 = 0
• Burn-in specifications: Wafer level burn-in
• Lead-free (Sn 100%), halogen-free*3
*1. Refer to " Endurance" for details.
*2. For each address (Word: 8-bit)
*3. Refer to " Product Name Structure" for details.
Packages
• 8-Pin SOP (JEDEC)
1
4
5
8
(5.0 × 6.0 × t1.75 mm)
• 8-Pin TSSOP
1
4
5
8
(3.0 × 6.4 × t1.1 mm)
Remark Refer to "3. Product name list" in " Product Name Structure" for details of package and product.
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
2
Block Diagram
Mode
Decoder
Status RegisterAddress Register
Data Register
WP
CS
HOLD
SI
SCK
SO
VCC
GND
Memory
Cell
Array
Status
Memory Cell Array
Voltage Detector
Read Circuit
Clock Counter
Y Decoder
X Decoder
Input Control Circuit
Output
Control
Circuit
Step-up Circuit
Page Latch
Figure 1
Product Name Structure
1. Product name
S-25A128B 0A − xxxx U 3
Environmental code
U: Lead-free (Sn 100%), halogen-free
Fixed
Product name
S-25A128B: 128 K-bit
Fixed
Package name (abbreviation) and IC packing specification*1
J8T2: 8-Pin SOP (JEDEC), Tape
T8T2: 8-Pin TSSOP, Tape
*1. Refer to the tape drawing.
Remark This IC is wafer level burn-in specification.
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 3
2. Packages
Table 1 Packag e Drawing Codes
Package Name Dimension Tape Reel
8-Pin SOP (JEDEC) FJ008-A-P-SD FJ008-D-C-SD FJ008-D-R-S1
8-Pin TSSOP FT008-A-P-SD FT008-E-C-SD FT008-E-R-S1
3. Product name list
Table 2
Product Name Capacity Package Quantity
S-25A128B0A-J8T2U3 128 K bit 8-Pin SOP (JEDEC) 4000 pcs / reel
S-25A128B0A-T8T2U3 128 K bit 8-Pin TSSOP 4000 pcs / reel
Remark This IC is wafer level burn-in specification.
Pin Configurations
1. 8-Pin SOP (JEDEC)
Table 3
Pin No. Symbol Description
1 CS *1 Chip select input
2 SO Serial data output
3 WP *1 Write protect input
4 GND Ground
5 SI*1 Serial data input
6 SCK*1 Serial clock input
7 HOLD*1 Hold input
8 VCC Power supply
7
6
5
8
2
3
4
1
Top view
Figure 2
2. 8-Pin TSSOP
Table 4
Pin No. Symbol Description
1 CS *1 Chip select input
2 SO Serial data output
3 WP *1 Write protect input
4 GND Ground
5 SI*1 Serial data input
6 SCK*1 Serial clock input
7 HOLD*1 Hold input
8 VCC Power supply
7
6
5
8
2
3
4
1
Top view
Figure 3
*1. Do not use it in "High-Z".
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
4
Absolute Maximum Ratings Table 5
Item Symbol Absolute Maximum Rating Unit
Power supply voltage VCC −0.3 to +6.5 V
Input voltage VIN −0.3 to +6.5 V
Output voltage VOUT −0.3 to VCC + 0.3 V
Operation ambient temperature Topr −40 to +125 °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 6
Ta = −40°C to +125°C
Item Symbol Condition Min. Max.
Unit
Read 2.5 5.5 V
Power supply voltage VCC Write 2.5 5.5 V
High level input voltage VIH V
CC = 2.5 V to 5.5 V 0.7 × VCC V
CC + 1.0 V
Low level input voltage VIL V
CC = 2.5 V to 5.5 V −0.3 0.3 × VCC V
Pin Capacitance Table 7 (Ta = +25°C, f = 1.0 MHz, V CC = 5.0 V)
Item Symbol Condition Min. Max. Unit
Input capacitance CIN VIN = 0 V (CS, SCK, SI, WP , HOLD) － 8 pF
Output capacitance COUT V
OUT = 0 V (SO) － 10 pF
Endurance
Table 8
Item Symbol Operation Ambient Temperature Min. Max. Unit
Ta = +25°C 106 － cycle / word*1
Ta = −40°C to +85°C 7 × 105 － cycle / word*1
Ta = −40°C to +105°C 5 × 105 － cycle / word*1
Endurance NW
Ta = −40°C to +125°C 3 × 105 － cycle / word*1
*1. For each address (Word: 8-bit)
Data Retention Table 9
Item Symbol Operation Ambient Temperature Min. Max. Unit
Ta = +25°C 100
－ year
Data retention － Ta = −40°C to +125°C 50
－ year
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 5
DC Electrical Characteristics
Table 10
Ta = −40°C to +125°C
VCC = 2.5 V to 4.5 V
fSCK = 6.5 MHz VCC = 4.5 V to 5.5 V
fSCK = 6.5 MHz
Item Symbol Condition
Min. Max. Min. Max.
Unit
Current consumption
(read) ICC1 No load at SO pin － 2.0 － 2.5 mA
Table 11
Ta = −40°C to +125°C
VCC = 2.5 V to 5.5 V
fSCK = 6.5 MHz
Item Symbol Condition
Min. Max.
Unit
Current consumption
(write) ICC2 No load at SO pin － 4.0 mA
Table 12
Ta = −40°C to +125°C
VCC = 2.5 V to 4.5 V VCC = 4.5 V to 5.5 V
Item Symbol Condition Min. Max. Min. Max.
Unit
Standby current
consumption ISB
CS = VCC,
SO = Open
Other inputs are
VCC or GND
－ 8.0 － 10.0 μA
Input leakage current ILI V
IN = GND to VCC － 2.0 － 2.0 μA
Output leakage current ILO V
OUT = GND to VCC － 2.0 － 2.0 μA
VOL1 I
OL = 2.0 mA － － － 0.4 V
Low level
output voltage VOL2 I
OL = 1.5 mA － 0.4 － 0.4 V
VOH1 I
OH = −2.0 mA － － 0.8 × VCC － V
High level
output voltage VOH2 I
OH = −0.4 mA 0.8 × VCC － 0.8 × VCC － V
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
6
AC Electrical Characteristics
Table 13 Measurement Conditions
Input pulse voltage 0.2 × VCC to 0.8 × VCC
Output reference voltage 0.5 × VCC
Output load 100 pF
Table 14
Ta = −40°C to +125°C
VCC = 2.5 V to 5.5 V
Item Symbol
Min. Max.
Unit
SCK clock frequency fSCK － 6.5 MHz
CS setup time during CS falling tCSS.CL 65 － ns
CS setup time during CS rising tCSS.CH 65 － ns
CS deselect time tCDS 65
－ ns
CS hold time during CS falling tCSH.CL 65 － ns
CS hold time during CS rising tCSH.CH 65 － ns
SCK clock time "H" *1 tHIGH 65 － ns
SCK clock time "L"*1 tLOW 65 － ns
Rising time of SCK clock*2 tRSK － 1 μs
Falling time of SCK clock*2 tFSK － 1 μs
SI data input setup time tDS 15
－ ns
SI data input hold time tDH 20
－ ns
SCK "L" hold time during HOLD rising tSKH.HH 45 － ns
SCK "L" hold time during HOLD falling tSKH.HL 30 － ns
SCK "L" setup time during HOLD falling tSKS.HL 0 － ns
SCK "L" setup time during HOLD rising tSKS.HH 0 － ns
Disable time of SO output*2 tOZ － 75 ns
Delay time of SO output tOD － 50 ns
Hold time of SO output tOH 0
－ ns
Rising time of SO output*2 tRO － 30 ns
Falling time of SO output 2 tFO － 30 ns
Disable time of SO output during HOLD falling*2 tOZ.HL － 75 ns
Delay time of SO output during HOLD rising*2 tOD.HH － 50 ns
WP setup time tWS1 0
－ ns
WP hold time tWH1 0 － ns
WP release / setup time tWS2 0
－ ns
WP release / hold time tWH2 20 － ns
*1. The clock cycle of the SCK clock (f requency fSCK) is 1 / fSCK μs. This clock cycle is determined by a combination of
several AC characteristics. Note that the clock cycle cannot be set as (1 / fSCK) = tLOW (min.) + tHIGH (min.) by
minimizing the SCK clock cycle time.
*2. These are values of sample and not 100% tested.
Table 15
Ta = −40°C to +125°C
VCC = 2.5 V to 5.5 V
Item Symbol
Min. Max.
Unit
Write time tPR － 5.0 ms
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 7
SO
t
CSH.CL
SCK
CS
SI
t
CSS.CL
t
DS
t
DH
MSB IN LSB IN
t
CSH.CH
t
CSS.CH
t
CDS
t
FSK
t
RSK
High-Z
Figure 4 Serial Input Timing
SO
SCK
HOLD
CS
SI
t
SKH.HL
t
OZ.HL
t
OD.HH
t
SKH.HH
t
SKS.HL
t
SKS.HH
Figure 5 Hold Timing
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
8
SO
SCK
CS
SI
tHIGH
tOH
tRO
tOZ
tLOW
tSCK
tOD
tFO
tOD tOH
ADDR
LSB IN
LSB OUT
Figure 6 Serial Output Timing
WP
CS
t
WH1
t
WS1
Figure 7 Valid Timing in Write Protect
WP
CS
t
WH2
t
WS2
Figure 8 Invalid Timing in Write Protect
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 9
Pin Functions
1. CS (chip select input) pin
This is an input pin to set a chip in the select status. In the "H" input level, this IC is in the non-select status and its
output is "High-Z". This IC is in standby as long as it is not in write inside. This IC goes in active by setting the chip
select to "L". Input any instruction code after power-on and a falling of chip select.
2. SI (serial data input) pin
This pin is to input serial data. T his pin receives an instruction code, an address and write data. This pin latc hes data
at rising edge of serial clock.
3. SO (serial data output) pin
This pin is to output serial data. The data output changes at falling edge of serial clock.
4. SCK (serial clock input) pin
This is a clock input pin to set the t iming of serial data. An inst ruction code, an address and write data are received at
a rising edge of clock. Data is output during falling edge of clock.
5. WP (write protect input) pin
Write protect is purposed to protect the area size against the write instruction (BP1, BP0 in the status register). Fix
this pin "H" or "L" not to set it in the floating state.
Refer to " Protect Operation" for details.
6. HOLD (hold input) pin
This pin is used to pause serial communications without setting this IC in the non-select status.
In the hold status, the serial output goes in "High-Z ", the serial input and the serial clock go in "Don' t care". During the
hold operation, be sure to set this IC in active by setting the chip select (CS pin) to "L".
Refer to " Hold Operation" for details.
Initial Shipment Data
Initial shipment data of all addresses is "FFh".
Moreover, initial shipment data of the st atus register nonvolatile memory is as follows.
• SRWD = 0
• BP1 = 0
• BP0 = 0
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
10
Instruction Set
Table 16 is the list of instruction for this IC. The instruct ion is able to be input by changing the CS pin "H" to "L". I nput
the instruction in the MSB first. Each instruction code is organized with 1-byte as shown below. If this IC receives any
invalid instruction code, this IC goes in the non-select status.
Table 16 Instruction Set
Instruction Code Address Data
Instruction Operation SCK Input Clock
1 to 8 SCK Input Clock
9 to 16 SCK Input Clock
17 to 24 SCK Input Clock
25 to 32
WREN Wr ite enable 0000 0110 － － －
WRDI Write disable 0000 0100 － － －
RDSR Read the status
register 0000 0101 b7 to b0 output*1 － －
WRSR Write in the status
register 0000 0001 b7 to b0 input － －
READ Read memory data 0000 0011 A15 to A8*2 A7 to A0 D7 to D0 output*3
WRITE Write memory data 0000 0010 A15 to A8*2 A7 to A0 D7 to D0 input
*1. Sequential data reading is possible.
*2. The higher addresses A15 to A14 = Don't care.
*3. After outputting data in the specified address, data in the following address is output.
Operation
1. Status register
The status register's organization is below. The status register can write and read by a specific instruction.
SRWD 0
b7 b6
0
b5
0
b4
BP1
b3
BP0
b2
WEL
b1
WIP
b0
Status Register Write Disable Block Protect Write Enable Latch
Write In Progress
Figure 9 Organization of Status Register
The status / control bits of the status register as follows.
1. 1 SRWD (b7) : Status Register Write Disable
Bit SRWD operates in conjunction with the write protect signal ( WP ). With a combination of bit SRW D and signal
WP (SRWD = "1", WP = "L"), this IC goes in Hardware Protect status. In this case, the bits composed of the
nonvolatile memory in the status register (SRWD, BP1, BP0) go in read only, so that the WRSR instruction is not
be performed.
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 11
1. 2 BP1, BP0 (b3, b 2) : Bl ock Protect
Bit BP1 and BP0 are composed of the nonvolatile memory. The area size of Software Protect against WRITE
instruction is defined by them. Rewriting these bits is possible by the WRSR instruction. To protect the memory
area against the WRITE instruction, set either or both of bit BP1 and BP0 to "1". Rewriting bit BP1 and BP0 is
possible unless they are in Hardware Protect mode. Refer to " Protect Operation" for details of Block Protect.
1. 3 WEL (b1) : W rite Enable Latch
Bit WEL shows the status of internal Write Enable Latch. Bit WEL is set by the WREN instruction only. If bit WEL
is "1", this is the status that W rite Enable Latch is set. If bit WEL is "0", Wr ite Enable Latch is in reset, so that this
IC does not receive the WRIT E or WRSR instruction. Bit WEL is reset af t er these operations;
• The power supply voltage is dropping
• At power-on
• After performing WRDI
• After the completion of write operation by the WRSR instruction
• After the completion of write operation by the WRITE instruction
1. 4 WIP (b0) : W ri t e In Progress
Bit WIP is read only and shows whether the internal memory is in the write operation or not by the WRITE or
WRSR instruction. Bit WIP is "1" during the write operation but "0" during any other status. Figure 10 shows the
usage example.
000 000 000 00
S
R
W
D
B
P
1
B
P
0
S
R
W
D
B
P
1
B
P
0
S
R
W
D
B
t
PR
P
1
B
P
0
WEL, WIP WEL, WIP WEL, WIP
CS
SI
SO
RDSR instruction RDSR instruction RDSR instruction
RDSR RDSR RDSR
11 11
WRITE or WRSR instruction
D2 D1D0
Figure 10 Usage Example of WEL, WIP Bits during Write
2. Write enable (WREN)
Before writing data (WRITE and WRSR), be sure to set bit Write Enable Latch (WEL). This instruction is to set bit
WEL. Its operat ion is below.
After selecting this IC by the chip select ( CS), input the instruction code from serial data input (SI). T o set bit WEL,
set this IC in the non-select status by CS at the 8t h clock of the serial clock (SCK). T o cancel the W REN instruct ion,
input the clock different from a specif ied value (n = 8 clock) while CS is in "L".
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
12
SO
SCK
WP
CS
SI
Instruction
High-Z
12345678
High / Low
Figure 11 WREN Operation
3. Write disable (WRDI)
The WRDI instruction is one of ways to reset bit Write Enable Latch (WEL). Af ter selecting this IC by the chip select
(CS ), input the instruction code from serial data input (SI) .
To reset bit WEL, set this IC in the non-select status by CS at the 8th clock of the serial clock.
To cancel the WRDI instruction, input the clock different fr om a specified value (n = 8 clock) while CS is in "L".
Bit WEL is reset after the operations shown below.
• The power supply voltage is dropping
• At power-on
• After performing WRDI
• After the completion of write operation by the WRSR instruction
• After the completion of write operation by the WRITE instruction
SO
SCK
WP
CS
SI
Instruction
High-Z
12345678
High / Low
Figure 12 WRDI Operation
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 13
4. Read the status register (RDSR)
Reading data in the status register is possible by the RDSR instruction. During the write operation, it is possible to
confirm the progress by checking bit WIP.
Set the chip select (CS ) "L" first. After that, input the instruction code from serial data input (SI). The status of bit in
the status register is output f rom serial data output (SO). Sequential read is available for the status register. To stop
the read cycle, set CS to "H".
It is possible to read the status register always. The bits in it are valid and can be read by RDSR even in the write
cycle.
However, during the write cycle in progress, t he nonvolatile bits SRWD, BP1, BP0 are fixed in a certain value. These
updated values of bit can be obtained by inputting another new RDSR instruction af ter the write cycle has completed.
Contrarily, two of read only bits WEL and WIP are being updated while the writ e cycle is in progress.
SO
SCK
WP
CS
SI
Instruction
High-Z
12345678
High / Low
9 10111213141516
Outputs Data in the Status Register
b7 b6 b5 b7b0b1b2b3b4
Figure 13 RDSR Operation
5. Write in the status register (WRSR)
The values of status register (SRWD, BP1, BP0) can be rewrit ten by inputting the WRSR instruction. But b6, b5, b4,
b1, b0 of status register cannot be rewritten. b6 to 4 are always data "0" when reading the status register.
Before inputting the WRSR instruction, set bit WEL by the WREN instruction. The operation of WRSR is shown
below.
Set the chip select (CS ) "L" first. After that, input the instruction code and data from serial data input (SI). To start
WRSR write (tPR), set the chip select (CS ) to "H" after inputting data or before inputting a rising of the next serial
clock. It is possible to confirm the operation status by reading the value of bit WIP during WRSR write. Bit WIP is "1"
during write, "0" during any other status. Bit WEL is reset when write is completed.
With the WRSR instruction, the values of BP1 and BP0; which determine the area size the users can handle as the
Read only memory; can be changed. Besides bit SRWD can be set or reset by the WRSR instruction depending on
the status of write protect ( WP ). With a combination of bit SRWD and write protect ( WP ), this IC can be set in
Hardware Protect mode (HPM). In this case, the WRSR instruction is not be performed (Refer to " Protect
Operation").
Bit SRWD and BP1, BP0 keep the value which is the one prior to the WRSR instruction during the WRSR inst ruction.
The newly updated value is changed when the WRSR instruction has completed.
To cancel the WRSR instruction, input the clock different from a specif ied value (n = 16 clock) while CS is in "L".
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
14
SO
SCK
WP
CS
SI
Instruction
High-Z
12345678
High / Low
9 10111213141516
Inputs Data in the Status Register
b7 b6 b5 b0b1b2b3b4
Figure 14 WRSR Operation
6. Read memory data (READ)
The READ operation is shown below. Input the instruction code and the address from serial data input (SI) after
inputting "L" to the chip select (CS ). The input address is loaded to the internal address counter, and data in the
address is output from the serial data output (SO).
Next, by inputting the serial clock (SCK) keeping the chip select ( CS ) in "L", the address is automatically
incremented so that data in the following address is sequentially output. The address counter rolls over to the first
address by increment in the last address.
To finish the read cycle, set CS to "H". It is possible to raise the chip select always during the cycle. During write,
the READ instruction code is not be accepted or operated.
SO
SCK
WP
CS
SI
Instruction
High-Z
12345678
High / Low
91011 2122232425
16-bit Address
A15 A14 A13 A0A1A2A3
Outputs the First Byte
D4D5D6D7
26 27 28 29 30 31 32
D0D1D2D3 D7
Outputs
the Second
Remark The higher addresses A15 to A14 = Don't care.
Figure 15 READ Operation
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 15
7. Write memory data (WRITE)
Figure 16 shows the timing chart when inputting 1-byte data. Input the instruction code, the address and data from
serial data input (SI) after inputt ing "L" to the chip select (CS ). To start WRITE (tPR), set the chip select (CS) to "H"
after inputting data or before inputting a rising of the next serial clock. Bit WIP and WEL are reset to "0" when write
has completed.
This IC can Page write of 64 bytes. Its function to transmit data is as same as Byte write basically, but it operates
Page write by receiving sequential 8-bit write data as much data as page size has. Input the instruction code, the
address and data from serial data input (SI) after inputting "L" in CS , as the WRITE operation (page) shown in
Figure 17. Input the next data while keeping CS in "L". After that, repeat inputting dat a of 8-bit sequentially. At the
end, by setting CS to "H", t he WRITE operation starts (tPR).
6 of the lower bits in the address are automatically incremented every time when receiving write data of 8-bit. Thus,
even if write data exceeds 64 bytes, the higher bits in the address do not change. And 6 of lower bit s in the address
roll over so that write data which is previously input is overwritt en.
These are cases when the WRITE instruction is not accepted or operated.
• Bit WEL is not set to "1" (not set to "1" beforehand immediately before the WRITE instruction)
• During WRITE operation
• The address to be written is in the protect area by BP1 and BP0
To cancel the WRIT E instruction, input the clock different fr om a specified value (n = 24 + m × 8 clock) while CS is
in "L".
SO
SCK
WP
CS
SI
Instruction
High-Z
12345678
High / Low
91011 2122232425
16-bit Address
A15 A14 A13 A0A1A2A3
Data Byte 1
D4D5D6D7
26 27 28 29 30 31 32
D0D1D2D3
Remark The higher addresses A15 to A14 = Don't care.
Figure 16 WRITE Operation (1 Byte)
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
16
SO
SCK
WP
CS
SI
Instruction
High-Z
12345678
High / Low
9 1011 22232425
16-bit Address (n)
A15 A14 A13
A0A1A2
Data Byte (n) Data Byte (n + x)
D4D5D6D7
26 27 28 29 30 31 32
D0D1D2D3 D0D1D2D3
D4
Remark The higher addresses A15 to A14 = Don't care.
Figure 17 WRITE Operation (Page)
Protect Operation
Table 17 shows the block sett ings of write protect. Table 18 shows the protect operation for t his IC. As long as bit SRW D,
the Status Register write Disable bit , in the status register is reset to "0" (it is in reset before the shipment), t he value of
status register can be changed.
These are two statues when bit SRWD is set to "1".
• Write in the status register is possible; write protect ( WP ) is in "H".
• Write in the status register is impossible; write protect ( WP ) is in "L". Therefore t he write protect area which is set by
protect bit (BP1, BP0) in the status regist er cannot be changed.
These operations are to set Hardware Protect (HPM).
• After setting bit SRWD, set write protect (WP ) to "L".
• Set bit SRWD completed setting write protect ( WP ) to "L".
The timing during the cycle write to the status register is showed in "Figure 7 Valid Timing in Write Protect" and
"Figure 8 Invalid Timing in Write Protect".
By inputting "H" to write protect ( WP ), Hardware Protect (HPM) is released. If the write protect ( WP ) is "H", Hardware
Protect (HPM) does not function, Soft ware Protect (SPM) which is set by the protect bits in the status register (BP1, BP0)
only works.
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 17
Table 17 Block Settings of Write Prot ect
Status Register
BP1 BP0
Area of Write Protect Address of Write Protect Block
0 0 0% None
0 1 25% 3000h to 3FFFh
1 0 50% 2000h to 3FFFh
1 1 100% 0000h to 3FFFh
Table 18 Protect Operation
Mode WP Pin Bit SRWD Bit WEL Write Protect Block General Block Status Register
1 X 0
Write disable Wr ite disable Write disable
1 X 1
Write disable Write enable Write enable
X 0 0
Write disable Wr ite disable Write disable
Software Protect
(SPM) X 0 1
Write disable Write enable Write enable
0 1 0
Write disable Wr ite disable Write disable
Hardware Protect
(HPM) 0 1 1 Write disable Write enable Write disable
Remark X = Don't care
Hold Operation
The hold operation is used to pause serial communications without setting this IC in the non-select status. In the hold
status, the serial data output goes in "High-Z", and both of the serial data input and the serial clock go in "Don't care". Be
sure to set the chip select (CS) to "L" to set this IC in the select status during the hold status.
Generally, during the hold status, this IC holds the select status. But if setting this IC in the non-select status, the users
can finish the operation even in progress.
Figure 18 shows the hold operation.
These are two statuses when the serial clock (SCK) is set to "L".
• If setting hold (HOLD) to "L", hold (HOLD) is switched at the same time the hold status starts.
• If setting hold (HOLD) to "H", hold (HOLD) is switched at the same time the hold status ends.
These are two statuses when the serial clock (SCK) is set to "H".
• If setting hold (HOLD) to "L", the hold status starts when the serial clock goes in "L" after hold (HOLD) is switched.
• If setting hold (HOLD) to "H", the hold status ends when the serial clock goes in "L" after hold (HOLD) is switched.
SCK
HOLD
Hold status Hold status
Figure 18 Hold Operation
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
S-25A128B Rev.1.1_00
Seiko Instruments Inc.
18
Write Protect Function during the Low Power Supply Voltage
This IC has a built-in detection circuit which operates with the low power supply voltage. This IC cancels the write
operation (WRITE, WRSR) when the power supply voltage drops and power-on, at the same time, goes in the write
protect status (WRDI) automatically to reset bit WEL. Its detection and release voltages are 1.20 V typ. (Refer to Figure
19).
To operate write, after the power supply voltage dropped once but rose to the voltage level which allows write again, be
sure to set the write Enable Latch bit (WEL) before operating write (WRITE, WRSR).
In the write operation, data in the address written during the low power supply voltage is not assured.
Cancel the write instruction
Set in write protect (WRDI) automatically
Release voltage (+VDET)
1.20 V typ.
Detection voltage (−VDET)
1.20 V typ.
Power supply voltage
Figure 19 Operation during the Low Power Supply Voltage
Input Pin and Output Pin
1. Connection of input pin
All input pins in this IC have the CMOS structure. Do not set these pins in "High-Z" during operation when you design.
Especially, set the CS input pin in the non-select status "H" during power-on/off and standby. The error write does
not occur as long as the CS pin is in the non-select status "H". Set the CS pin to VCC via a resistor (the pull-up
resistor of 10 kΩ to 100 kΩ).
If the CS pin and the SCK pin change from "L" to "H" simultaneously, data may be input from the SI pin.
To prevent the error for sure, it is recommended to pull down the SCK pin to GND. In addition, it is recommended to
pull up the SI pin, the WP pin and the HOLD pin to VCC, or pull down these pins to GND, respectively. Connecting
the WP pin and the HOLD pin to VCC directly is also possible when these pins are not in use.
2. Equivalent circuit of input pin and output pin
Figure 20 and Figure 21 show the equivalent circuits of input pins in this IC. A pull-up and pull-down elements are
not included in each input pin, pay attention not to set it in the floating state when you design.
Figure 22 shows the equivalent circuit of the output pin. T his pin has the tri-state output of "H" / "L" / "High-Z".
2. 1 Input pin
CS, SCK
Figure 20 CS , SCK Pin
125°C OPERATION SPI SERIAL E2PROM FOR AUTOMOTIVE
Rev.1.1_00 S-25A128B
Seiko Instruments Inc. 19
SI, WP, HOLD
Figure 21 SI, WP , HOLD Pin
2. 2 Output pin
SO
V
CC
Figure 22 SO Pin
Precautions
• 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 this IC's pins may occur malfunction by short-circuit between pins. Especially, in
occasions like picking this IC up from low temperature tank during the evaluation. Be sure that not remain frost on t his
IC's pins to prevent malfunction by short-circuit.
Also attention should be paid in using on environment, which is easy to dew for the same reason.
• 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.
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. 4,000
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-S1-1.0
FJ008-D-R-S1-1.0
No.
TITLE
SCALE
UNIT
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
mm
No.
TITLE
SCALE
UNIT
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
mm
No.
TITLE
SCALE
UNIT
Seiko Instruments Inc.
Enlarged drawing in the central part
2±0.5
ø13±0.5
ø21±0.8
13.4±1.0
17.5±1.0
4,000
QTY.
TSSOP8-E-Reel
FT008-E-R-S1-1.0
mm
No. FT008-E-R-S1-1.0
www.sii-ic.com
• 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 approp riate governmental authority.
• Use of the information described herein for other purposes and/or reproduction or copying without the
express permissi on 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 vehicle s, without prior written permission of Seiko Instruments Inc.
• The products described herein are not designed to be radiation-proof .
• 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 comm unity damage that may ensue.
