BR25S256F-W_技术文档

High Reliability Series Serial EEPROMs

SPI BUS

BR25□□□□family

BR25S□□□Series

No.10001EBT08

●Description

^BR25S□□□ series is a serial EEPROM of SPI BUS interface method.

●Features

1) High speed clock action up to 20MHz (Max.)

2) Wait function by HOLDB terminal

3) Part or whole of memory arrays settable as read only memory area by program

4) 1.7～5.5V single power source action most suitable for battery use

5) Page write mode useful for initial value write at factory shipment

6) Highly reliable connection by Au pad and Au wire

7) For SPI bus interface (CPOL, CPHA) = (0, 0), (1, 1)

8) Auto erase and auto end function at data rewrite

9) Low current consumption

At write action (5V)

At read action (5V)

At standby action (5V)

:

1.5mA (Typ.)

1.0mA (Typ.)

0.1μA (Typ.)

10) Address auto increment function at read action

11) Write mistake prevention function

Write prohibition at power on

Write prohibition by command code (WRDI)

Write prohibition by WPB pin

Write prohibition block setting by status registers (BP1, BP0)

Write mistake prevention function at low voltage

12) SOP8/SOP-J8/SSOP-B8/TSSOP-B8/MSOP8/TSSOP-B8J/VSON008X2030 Package

13) Data at shipment Memory array: FFh, status register WPEN, BP1, BP0 : 0

14) Data kept for 40 years

15) Data rewrite up to 1,000,000 times

●Page Write

Page

32Byte

64Byte

BR25S320-W

BR25S640-W

BR25S128-W

BR25S256-W

Part Number

^●BR25S□□□ series

Power source

VSON008

X2030

Capacity Bit format

SOP8

SOP-J8 SSOP-B8 TSSOP-B8 MSOP8 TSSOP-B8J

voltage

32Kbit

64Kbit

4K×8

8K×8

1.7V～5.5V

●

128Kbit

256Kbit

16K×8

32K×8

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2010.12 - Rev.B

1/18

Technical Note

BR25S□□□Series

●Absolute maximum ratings (Ta=25°C)

●Memory cell characteristics (Ta=25°C , Vcc=1.7V～5.5V)

Parameter Symbol

Limits

-0.3～+6.5

450(SOP8)

Unit

V

Limits

Min.

Parameter

Unit

Impressed

Vcc

Min.

voltage

Number of

*1

*2

*3

*4

*5

*6

*7

1,000,000

－

Time

Year

data rewrite times ^*1

450(SOP-J8)

*1

Data hold years

40

－

300(SSOP-B8)

330(TSSOP-B8)

310(MSOP8)

*1 Not 100% TESTED

Permissible

Pd

mW

dissipation

●Recommended action conditions

310(TSSOP-B8J)

300(VSON008X2030)

Parameter

Power source voltage

Input voltage

Symbol

V_CC

V_IN

Limits

1.7～5.5

0～Vcc

Unit

V

Storage

temperature

range

Tstg

-65～+125

℃

●Input / output capacity (Ta=25°C, frequency=5MHz)

Operating

temperature

range

Terminal

voltage

Topr

-40～+85

℃

Parameter

Input capacity ^*1

Output capacity ^*1

Symbol Conditions Min. Max. Unit

C_IN

V_IN=GND

－

8

pF

－

-0.3～Vcc+0.3

V

C_OUTV_OUT=GND －

*1

Not 100% TESTED.

* When using at Ta=25℃ or higher, 4.5mW(*1, *2),

3.0mW(*3, *7),3.3mW(*4), 3.1mW(*5, *6) to be reduced per 1℃

●Electrical characteristics (Unless otherwise specified, Ta=-40～+85°C, Vcc=1.7～5.5V)

Limits

Typ.

Parameter

Symbol

Unit

Conditions

Min.

Max.

“H” Input Voltage1

VIH1

VIL1

0.7xVcc

－

Vcc+0.3

V

1.7≦Vcc≦5.5V

“L” Input Voltage1

-0.3

0

－

0.3xVcc

0.4

1.7≦Vcc≦5.5V

“L” Output Voltage1

“L” Output Voltage2

“H” Output Voltage1

“H” Output Voltage2

Input Leakage Current

Output Leakage Current

VOL1

VOL2

IOL=2.1mA, 2.5≦Vcc<5.5V

IOL=1.0mA, 1.7≦Vcc<2.5V

IOH=-0.4mA, 2.5V≦Vcc<5.5V

IOH=-100µA, 1.7≦Vcc<2.5V

0

0.2

VOH1 Vcc-0.2

VOH2 Vcc-0.2

Vcc

1

ILI

-1

μA V_IN=0～Vcc

ILO

1

μA V_OUT=0～Vcc, CSB=Vcc

*1

0.5

1

1.5

2

3

Vcc=1.8V, fSCK=5MHz, tE/W=5ms

mA

ICC1

ICC2

ICC3

ICC4

ICC5

ICC6

ICC7

ICC8

ICC9

ICC10

ISB

－

*2

*1

*2

*1

*2

Byte Write, Page Write, Write Status register

Vcc=2.5V, fSCK=10MHz, tE/W=5ms

Byte Write, Page Write, Write Status register

Vcc=5.5V, fSCK=20MHz, tE/W=5ms

Byte Write, Page Write, Write Status register

Vcc=1.8V, fSCK=5MHz, SO=OPEN

Read, Read Status Register

Operating Current Write

mA

μA

1

Vcc=2.5V, fSCK=2MHz, SO=OPEN

Read, Read Status Register

Vcc=2.5V, fSCK=5MHz, SO=OPEN

Read, Read Status Register

Vcc=2.5V, fSCK=10MHz, SO=OPEN

Read, Read Status Register

Vcc=5.5V, fSCK=5MHz, SO=OPEN

Read, Read Status Register

Vcc=5.5V, fSCK=10MHz, SO=OPEN

Read, Read Status Register

Vcc=5.5V, fSCK=20MHz, SO=OPEN

Read, Read Status Register

Vcc=5.5V, SO=OPEN

CSB=HOLDB=WPB=Vcc, SCK=SI=Vcc or GND

1.5

2

Operating Current Read

2

4

8

Standby Current

2

*1 BR25S320/640-W

*2 BR25S128/256-W

○

Radiation resistance design is not made

www.rohm.com

2010.12 - Rev.B

2/18

Technical Note

BR25S□□□Series

●Block diagram

VOLTAGE

1

2

3

4

8

7

6

5

CSB

SO

Vcc

INSTRUCTION DECODE

CONTROL CLOCK

GENERATION

DETECTION

WRITE

INHIBITION

HIGH VOLTAGE

GENERATOR

HOLDB

SCK

SI

*1 12bit: BR25S320-W

INSTRUCTION

REGISTER

13bit: BR25S640-W

14bit: BR25S128-W

15bit: BR25S256-W

STATUS REGISTER

ADDRESS

WPB

GND

ADDRESS

DECODER

12～15bit ^*

1

12～15bit ^*

1

REGISTER

32～256K

EEPROM

DATA

READ/WRITE

AMP

8bit

REGISTER

Fig.1 Block diagram

●Operating timing characteristics (Ta=-40～+85°C, unless otherwise specified, load capacity C_L=30pF)

1.7≦Vcc<2.5V 1.8≦Vcc<2.5V 2.5≦Vcc<4.5V 4.5≦Vcc<5.5V

Symbol

Unit

Parameter

Min. Typ. Max. Min. Typ. Max. Min. Typ. Max. Min. Typ. Max.

fSCK

-

3

-

80

90

60

50

20

-

5

-

40

30

20

10

-

10

-

20

15

5

-

20 MHz

SCK frequency

tSCKWH 125

tSCKWL 125

-

ns

μs

ns

ms

SCK high time

-

SCK low time

tCS

250

100

-

CSB high time

tCSS

tCSH

-

CSB setup time

-

CSB hold time

tSCKS 100

tSCKH 100

-

SCK setup time

-

SCK hold time

tDIS

tDIH

tPD

30

-

SI setup time

50

-

125

-

5

-

SI hold time

-

80

-

40

-

20

-

Data output delay time

Output hold time

tOH

0

tOZ

-

200

-

80

-

40

-

20

-

Output disable time

HOLDB setting setup time

HOLDB setting hold time

HOLDB release setup time

HOLDB release hold time

Time from HOLDB to output High-Z

Time from HOLDB to output change

tHFS

tHFH

tHRS

tHRH

tHOZ

tHPD

tRC

100

0

100

-

20

0

-

10

0

-

5

-

100

-

0

-

100

-

20

-

10

-

5

-

100

1

80

1

50

5

40

1

40

5

-

20

1

20

5

-

*1

-

SCK rise time

*1

tFC

1

-

SCK fall time

*1

tRO

100

5

-

OUTPUT rise time

*1

tFO

-

OUTPUT fall time

Write time

tE/W

-

*1 NOT 100% TESTED

www.rohm.com

2010.12 - Rev.B

3/18

Technical Note

BR25S□□□Series

●Pin assignment and description

Terminal

name

Input

/Output

Vcc

HOLDB SCK

SI

Function

Power source to be connected

Vcc

GND

CSB

SCK

SI

-

All input / output reference voltage, 0V

Chip select input

BR25S320-W

BR25S640-W

BR25S128-W

BR25S256-W

Input

Serial clock input

Start bit, ope code, address, and serial data input

SO

Output Serial data output

Hold input

CSB

SO

WPB

GND

HOLDB

WPB

Input

Command communications may be suspended temporarily

(HOLD status)

Write protect input

Write command is prohibited

Write status register command is prohibited

Fig.2 Pin assignment diagram

Input

●Sync data input / output timing

tCS

tCSS

tCS

CSB

SCK

tSCKH

CSB

tSCKS

tCSH

tRC

tFC

tSCKWH

tSCKWL

tDIS

SCK

SI

tDIH

tPD

SI

tRO,tFO

tOZ

tOH

High-Z

SO

High-Z

SO

Fig.4

Input / Output timing

Fig.3 Input timing

SI is taken into IC inside in sync with data rise edge of

SCK. Input address and data from the most significant bit

MSB

SO is output in sync with data fall edge of SCK. Data is

output from the most significant bit MSB.

CSB ^"H"

"L"

tHFS tHFH

tHRS tHRH

SCK

SI

tDIS

n

n+1

n-1

tHOZ

Dn

tHPD

High-Z

SO

Dn+1

Dn

Dn-1

HOLDB

Fig.5

HOLD timing

●AC timing characteristics conditions

Limits

Parameter

Symbol

Unit

Min.

Typ.

Max.

Load capacity

C_L

-

30

50

pF

ns

V

Input rise time

-

Input fall time

-

Input voltage

-

0.2Vcc/0.8Vcc

0.3Vcc/0.7Vcc

Input / Output judgment voltage

-

V

●Characteristic data (The following characteristic data are Typ. Values.)

6

5

4

3

2

1

0

6

5

4

3

2

1

0

1

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

0.8

0.6

0.4

0.2

0

SPEC

0

1

2

3

4

5

6

0

1

2

3

4

5

6

0

1

2

3

4

5

6

IOL[mA]

Vcc[V]

Fig.6 "H" input voltage VIH(CSB,SCK,SI,HOLDB,WPB) Fig.7 ꢀ"L" input voltageꢀVIL(CSB,SCK,SI,HOLDB,WPB)

Fig.8ꢀ"L" output voltageꢀVOL1 (Vcc=2.5V)

ꢀ

www.rohm.com

2010.12 - Rev.B

4/18

Technical Note

BR25S□□□Series

●Characteristic data (The following characteristic data are Typ. Values.)

2.6

2.5

2.4

2.3

2.2

1.5

1

1.5

1

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

0.5

0

0.5

0

Ta=-40℃

Ta=25℃

Ta=85℃

SPEC

-0.5

0

0.4

0.8

1.2

0

1

2

3

4

5

6

0

1

2

3

4

5

6

IOH[mA]

Vcc[V]

VOUT[V]

Fig.9ꢀ"H" output voltageꢀVOH1 (Vcc=2.5V)

Fig.10ꢀInput leak current ILI(CSB,SCK,SI,HOLDB,WPB)

Fig.11ꢀOutput leak current ILO(SO)

4

3

2

1

0

10

8

4

3

2

1

0

DATA=00h

SPEC

DATA=00h

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

6

SPEC

4

2

0

1

2

3

4

5

6

0

1

2

3

4

5

6

0

1

2

3

4

5

6

Vcc[V]

Fig.14ꢀCurrent Consumption at READ operation ICC10

Fig.12ꢀCurrent consumption at WRITE operation ICC3

Fig.13ꢀCurrent Consumption at WRITE operation ICC3

(BR25S320/640-W)

(BR25S128/256-W)

1000

140

5

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

120

4

Ta=-40℃

100

80

60

40

20

0

Ta=25℃

100

10

1

3

SPEC

Ta=85℃

SPEC

2

1

SPEC

0

SPEC

2

-1

0

1

2

3

Vcc[V]

4

5

6

0

1

3

4

5

6

0

1

2

3

4

5

6

Vcc[V]

Fig.15ꢀCurrent Consumption at standby operation ISB

Fig.17 SCK high timeꢀtSCKWH

Fig.16ꢀSCK frequency fSCK

140

300

250

200

150

100

50

120

100

80

60

40

20

0

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

120

100

80

60

40

20

0

SPEC

0

1

2

3

4

5

6

0

1

2

3

4

5

6

0

1

2

3

4

5

6

Vcc[V]

Fig.20ꢀCSB setup timeꢀtCSS

Fig.19 CSB high timeꢀtCS

Fig.18 SCK low timeꢀtSCKWL

www.rohm.com

2010.12 - Rev.B

5/18

Technical Note

BR25S□□□Series

●Characteristic data (The following characteristic data are Typ. Values.)

50

40

30

20

10

0

120

100

80

60

40

20

0

60

50

40

30

20

10

0

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

Ta=25℃

Ta=85℃

SPEC

5

SPEC

-10

0

1

2

3

Vcc[V]

4

5

6

0

1

2

3

Vcc[V]

4

5

6

0

1

2

3

Vcc[V]

4

6

Fig.23ꢀSI hold timeꢀtDIH

Fig.22ꢀSI setup timeꢀtDIS

Fig.21ꢀCSB hold timeꢀtCSH

120

100

80

60

40

20

0

210

180

150

120

90

140

120

100

80

Ta=-40℃

Ta=25℃

Ta=85℃

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

SPEC

60

SPEC

60

40

SPEC

6

SPE

C

SPEC

4

30

SPEC

20

0

1

2

3

5

6

0

1

2

3

Vcc[V]

4

5

0

1

2

3

Vcc[V]

4

5

6

Vcc[V]

Fig.26ꢀHOLDB setting hold time tHFH

Fig.24ꢀData output delay time ｔPD

Fig.25ꢀOutput disable time tOZ

130

110

90

120

Ta=-40℃

Ta=25℃

Ta=85℃

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

100

80

60

40

20

0

100

80

60

40

20

0

SPEC

70

50

SPEC

30

SPEC

SPE

SPEC

4

SPEC

10

-10

0

1

2

3

5

6

0

1

2

3

4

5

6

0

1

2

3

Vcc[V]

4

5

6

Vcc[V]

Fig.27ꢀHOLDB release hold time tHRH

Fig.28ꢀTime from HOLDB to output High-Z tHOZ

Fig.29ꢀTime from HOLDB to output change tHPD

8

120

100

80

60

40

20

0

Ta=-40℃

Ta=25℃

Ta=85℃

Ta=-40℃

SPEC

Ta=-40℃

Ta=25℃

Ta=85℃

100

80

60

40

20

0

SPEC

Ta=25℃

Ta=85℃

6

4

2

0

SPEC

0

1

2

3

Vcc[V]

4

5

6

0

1

2

3

4

5

6

0

1

2

3

4

5

6

Vcc[V]

Fig.30 Output rise time tRO

Fig.31 Output fall time tFO

Fig.32 Write cycle time tE/W

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2010.12 - Rev.B

6/18

Technical Note

BR25S□□□Series

●Features

○Status registers

This IC has status register. The status register expresses the following parameters of 8 bits.

BP0 and BP1 can be set by write status register command. These 2 bits are memorized into the EEPROM, therefore are

valid even when power source is turned off.

Rewrite characteristics and data hold time are same as characteristics of the EEPROM.

WEN can be set by write enable command and write disable command. WEN becomes write disable status when power

source is turned off. R/B is for write confirmation, therefore cannot be set externally.

The value of status register can be read by read status register command.

1. Contexture of status register

Product number

BR25S320-W

bit 7

bit 6

0

bit 5

0

bit 4

0

bit 3

BP1

bit 2

BP0

bit 1

bit 0

BR25S640-W

BR25S128-W

BR25S256-W

―

WPEN

WEN

R/B

Memory

location

bit

Function

WPB pin enable / disable designation bit

WPEN=0=invalid

WPEN

EEPROM

WPEN=1=valid

BP1

BP0

EEPROM

registers

EEPROM write disable block designation bit

Write and write status register write enable / disable status confirmation bit

WEN

WEN=0=prohibited

WEN=1=permitted

Write cycle status (READY / BUSY) status confirmation bit

―

R/B=0=READY

registers

R/B

―

R/B=1=BUSY

2. Write disable block setting

Write disable block

BP1

BP0

BR25S320-W

None

BR25S640-W

None

BR25S128-W

None

BR25S256-W

None

0

1

0

1

0

1

C00h-FFFh

800h-FFFh

000h-FFFh

1800h-1FFFh

1000h-1FFFh

0000h-1FFFh

3000h-3FFFh

2000h-3FFFh

0000h-3FFFh

6000h-7FFFh

4000h-7FFFh

0000h-7FFFh

○WPB pin

By setting WPB=LOW, write command is prohibited. And the write command to be disabled at this moment is WRSR.

However, when write cycle is in execution, no interruption can be made.

Product number

BR25S320-W

BR25S640-W

BR25S128-W

BR25S256-W

WRSR

WRITE

Prohibition possible

but WPEN bit “1”

Prohibition

impossible

○HOLDB pin

By HOLDB pin, data transfer can be interrupted. When SCK=”0”, by making HOLDB from “1” into”0”, data transfer to

EEPROM is interrupted. When SCK = “0”, by making HOLDB from “0” into “1”, data transfer is restarted.

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2010.12 - Rev.B

7/18

Technical Note

BR25S□□□Series

●Command mode

Command

Contents

Ope code

0000

WREN

WRDI

READ

WRITE

RDSR

WRSR

Write enable command

Write disable command

Read command

Write command

Read status register command

Write status register command

0110

0100

0011

0010

0101

0001

●Timing chart

1. Write enable (WREN) / disable (WRDI) command

WREN (WRITE ENABLE): Write enable

WRDI (WRITE DISABLE): Write disable

CSB

SCK

SI

0

1

2

3

4

5

6

7

SCK

SI

0

1

2

3

4

5

6

7

0

1

0

1

0

High-Z

SO

High-Z

SO

Fig.33 Write enable command

Fig.34 Write disable command

This IC has write enable status and write disable status. It is set to write enable status by write enable command, and it is

set to write disable status by write disable command. As for these commands, set CSB LOW, and then input the

respective ope codes. The respective commands are accepted at the 7-th clock rise. Even with input over 7 clocks,

command becomes valid.

When to carry out write command, it is necessary to set write enable status by the write enable command. If write

command is input in the write disable status, the command is cancelled. And even in the write enable status, once write

command is executed, it gets in the write disable status. After power on, this IC is in write disable status.

2. Read command (READ)

Product

number

Address

length

A11-A0

CSB

SCK

SI

～～

BR25S320-W

BR25S640-W

BR25S128-W

BR25S256-W

10

0

1

2

3

4

5

6

7

8

9

11

23

24

30

31

A12-A0

A13-A0

A14-A0

～～

0

1

*

A14 A13 A12

A1 A0

～～

High-Z

D7 D6

D2 D1 D0

SO

Fig.35 Read command

By read command, data of EEPROM can be read. As for this command, set CSB LOW, then input address after read ope

code. EEPROM starts data output of the designated address. Data output is started from SCK fall of 23-th clock, and

from D7 to D0 sequentially. This IC has increment read function. After output of data for 1 byte (8bits), by continuing input

of SCK, data of the next address can be read. Increment read can read all the addresses of EEPROM. After reading data

of the most significant address, by continuing increment read, data of the most insignificant address is read.

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2010.12 - Rev.B

8/18

Technical Note

BR25S□□□Series

3. Write command (WRITE)

Product

number

Address

length

CSB

～～

0

1

2

3

4

5

6

7

8

10

11

23

24

30

31

9

SCK

BR25S320-W

BR25S640-W

BR25S128-W

BR25S256-W

A11-A0

A12-A0

A13-A0

A14-A0

～～

0

1

0

A14 A13 A12

A1

A0

D7 D6

D2

～～

D1

D0

SI

*

High-Z

～～

SO

＊=Don't Care

Fig.36 Write command

By write command, data of EEPROM can be written. As for this command, set CSB LOW, then input address and data

after write ope code. Then, by making CSB HIGH, the EEPROM starts writing. The write time of EEPROM requires time

of tE/W (Max 5ms). During tE/W, other than read status register command is not accepted. Set CSB HIGH between

taking the last data (D0) and rising the next SCK clock. At the other timing, write command is not executed, and this write

command is cancelled. This IC has page write function, and after input of data for 1 byte (8 bits), by continuing data input

without setting CSB HIGH, 2byte or more data can be written for one tE/W. The maximum number of write bytes is

specified per device of each capacity. Up to 64 arbitrary bytes can be written (in the case of BR25S128/256-W). In page

write, the insignificant 5 bit of the designated address is incremented internally at every time when data of 1 byte is input

and data is written to respective addresses. When data of the maximum bytes or higher is input, address rolls over, and

previously input data is overwritten.

4. Write status register, Read status register command (WRSR/RDSR)

CSB

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

SCK

bit7

WPEN

bit6

bit5

bit4

bit3

bit2

bit1

bit0

0

1

BP1 BP0

SI

*

High-Z

SO

*=Don't care

Fig.37 Write status register

Write status register command can write data of status register. The data can be written by this command are 3 bits, that

is, WPEN(bit7), BP1 (bit3) and BP0 (bit2) among 8 bits of status register. By BP1 and BP0, write disable block of

EEPROM can be set. As for this command, set CSB LOW, and input ope code of write status register, and input data.

Then, by making CSB HIGH, EEPROM starts writing. Write time requires time of tE/W as same as write. As for CSB rise,

set CSB HIGH between taking the last data bit (bit0) and the next SCK clock rising. At the other timing, command is

cancelled. Write disable block is determined by BP1 BP0, and the block can be selected from 1/4 , 1/2, and entire of

memory array (Refer to the write disable block setting table.). To the write disabled block, write cannot be made, and only

read can be made.

CSB

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

SCK

0

1

0

1

SI

bit7

WPEN

bit6

bit5

bit4

bit3

bit2

bit1

WEN

bit0

R/B

High-Z

0

BP1 BP0

SO

Fig.38 Read status register command

www.rohm.com

2010.12 - Rev.B

9/18

Technical Note

BR25S□□□Series

●WPB cancel valid area

WPB is normally fixed to “H” or “L” for use, but when WPB is controlled so as to cancel write status register command, pay

attention to the following WPB valid timing.

While write status register command is executed, by setting WPB = “L” in cancel valid area, command can be cancelled.

The area from command ope code to CSB rise at internal automatic write start becomes the cancel valid area. However,

once write is started, by any input write cycle cannot be cancelled. WPB input becomes Don’t Care, and cancellation

becomes invalid.

SCK

6

7

15

16

tE/W

Ope Code

Data

Data write time

Valid

(WRSR command is reset by WPB=L)

Invalid

Fig.39 WPB valid timing (At inputting WRSR command)

●HOLDB pin

By HOLDB pin, command communication can be stopped temporarily (HOLD status). The command communications are

carried out when the HOLDB pin is HIGH. To get in HOLD status, at command communication, when SCK=LOW, set the

HOLDB pin LOW. At HOLD status, SCK and SI become Don’t Care, and SO becomes high impedance (High-Z). To release

the HOLD status, set the HOLDB pin HIGH when SCK=LOW. After that, communication can be restarted from the point

before the HOLD status. For example, when HOLD status is made after A5 address input at read, after release of HOLD

status, by starting A4 address input, read can be restarted. When in HOLD status, keep CSB LOW. When it is set

CSB=HIGH in HOLD status, the IC is reset, therefore communication after that cannot be restarted.

www.rohm.com

2010.12 - Rev.B

10/18

Technical Note

BR25S□□□Series

●Method to cancel each command

○READ, RDSR

・Method to cancel : cancel by CSB = “H”.

Ope code

8 bits

Address

16 bits

Data

Ope code

8 bits

Cancel available in all areas of read mode

Cancel available in all

areas of rdsr mode

Fig.40 READ cancel valid timing

Fig.41 RDSR cancel valid timing

○WRITE、PAGE WRITE

Ope code

8bits

Address

16bits

Data

tE/W

a：Ope code or address input area

Cancellation is available by CSB=”H”.

b：Data input area (D7～D1 input area)

Cancellation is available by CSB=”H”.

c：Data input area (D0 area)

8bits

b

a

d

c

SCK

SI

In this area, cancellation is not available.

When CSB is set HIGH, write starts.

d：tE/W area

D7 D6 D5 D4 D3 D2 D1 D0

c

b

In the area c, by rising CSB, write starts.

While writing, by any input, cancellation cannot be made.

Fig.42 WRITE cancel valid timing

Note1) If Vcc is made OFF during write execution, designated address data is not guaranteed, therefore write it once again.

Note2) If CSB is rised at the same timing as that of the SCK rise, write execution / cancel becomes unstable, therefore, it is

recommended to rise in SCK = “L” area. As for SCK rise, assure timing of tCSS / tCSH or more.

○WRSR

14 15

16

17

SCK

SI

a：From ope code to 15-th clock rise

Cancellation is available by CSB=”H”.

D1

D0

b：From 15-th clock rise to 16-th clock rise (write enable area)

In this area, cancellation is not available.

When CSB is set HIGH, write starts.

a

b

c

tE/W

c

Ope code

8 bits

Data

8 bits

c：After 16-th clock rise.

Cancellation is available by CSB=”H”.

However, if write starts (CSB is rised)

a

in the area b, cancellation cannot be made by any means.

And, by inputting on SCK clock, cancellation cannot be made.

b

Fig.43 WRSR cancel valid timing

Note1) If Vcc is made OFF during write execution, designated address data is not guaranteed, therefore write it once

again

Note2) If CSB is rised at the same timing as that of the SCK rise, write execution / cancel becomes unstable, therefore, it

is recommended to rise in SCK = “L” area. As for SCK rise, assure timing of tCSS / tCSH or more.

○WREN/WRDI

6

7

8

SCK

a：From ope code to 7-th clock rise, cancellation is available by CSB = “H”.

b：Cancellation is not available 7-th clock.

Ope code

8 bits

a

b

Fig.44 WREN/WRDI cancel valid timing

www.rohm.com

2010.12 - Rev.B

11/18

Technical Note

BR25S□□□Series

●I/O peripheral circuits

In order to realize stable high speed operations, pay attention to the following input / output pin conditions.

○Input pin pull up, pull down resistance

When to attach pull up, pull down resistance to EEPROM input pin, select an appropriate value for the microcontroller

VOL, IOL with considering VIL characteristics of this IC.

V_CC－V_OLM

1. Pull up resistance

R_PU≧

･･･①

･･･②

I_OLM

V_ILE

V_OLM≦

Microcontroller

V_OLM

“L” output

I_OLM

EEPROM

V_ILE

R_PU

Example) When Vcc=5V, V_ILE=1.5V, V_OLM=0.4V, I_OLM=2mA,

from the equation ①,

5－0.4

2×10^-3

“L” input

R_PU≧

∴R_PU≧

2.3[kΩ]

Fig.45 Pull up resistance

With the value of Rpu to satisfy the above equation, V_OLM

becomes 0.4V or lower, and with V_ILE(=1.5V), the equation ② is

also satisfied.

・V_ILE:EEPROM V_ILspecifications

・V_OLM:Microcontroller V_OLspecifications

・I_OLM:Microcontroller I_OLspecifications

And, in order to prevent malfunction or erroneous write at power ON/OFF, be sure to make CSB pull up.

V_OHM

2.Pull down resistance

R_PD≧

･･･③

I_OHM

V_IHE

V_OHM≧

･･･④

Microcontroller

V_OHM

EEPROM

V_IHE

Example) When V_CC=5V, V_OHM=V_CC-0.5V, I_OHM＝0.4mA,

V_IHE=V_CC×0.7V, from the equation③,

5－0.5

R_PD

“H” output

I_OHM

“H” input

R_PD≧

0.4×10^-3

∴R_PD≧

11.3[kΩ]

Fig.46 Pull down resistance

Further, by amplitude VIHE, VILE of signal input to EEPROM, operation speed changes. By inputting Vcc/GND level

amplitude of signal, more stable high speed operations can be realized. On the contrary, when amplitude of 0.8VCC /

0.2Vcc is input, operation speed becomes slow.^*1

In order to realize more stable high speed operation, it is recommended to make the values of R_PU, R_PDas large as

possible, and make the amplitude of signal input to EEPROM close to the amplitude of VCC / GND level.

(^*1 In this case, guaranteed value of operating timing is guaranteed.)

○SO load capacity condition

Load capacity of SO output pin affects upon delay characteristic of SO output (Data output delay time, time from HOLDB

to High-Z, Output rise time, Output fall time.). In order to make output delay characteristic into better, make SO load

capacity small.

EEPROM

SO

C_L

Fig.47 SO load capacity

○Other cautions

Make the each wire length from the microcontroller to EEPROM input pin same length, in order to prevent setup / hold

violation to EEPROM, owing to difference of wire length of each input.

www.rohm.com

2010.12 - Rev.B

12/18

Technical Note

BR25S□□□Series

●Equivalent circuit

○Output circuit

internal

signal

SO

internal

signal

Fig.48 SO output equivalent circuit

○Input circuit

internal

signal

CSB

internal

signal

Fig.49 CSB input equivalent circuit

internal

signal

internal

signal

SI

SCK

Fig.51 SI input equivalent circuit

Fig.50 SCK input equivalent circuit

internal

signal

internal

signal

WPB

HOLDB

Fig.53 WPB input equivalent circuit

Fig.52 HOLDB input equivalent circuit

www.rohm.com

2010.12 - Rev.B

13/18

Technical Note

BR25S□□□Series

●Notes on power ON/OFF

○At standby

Set CSB “H”, and be sure to set SCK, SI input “L” or “H”. Do not input intermediate electric potantial.

○At power ON/OFF

When Vcc rise or fall, set CSB=”H” (=Vcc).

When CSB is “L”, this IC gets in input accept status (active). If power is turned on in this status, noises and the likes may

cause malfunction, erroneous write or so. To prevent these, at power ON, set CSB “H”. (When CSB is in “H” status, all

inputs are canceled.)

Vcc

CSB

Good example Bad example

Fig.54 CSB timing at power ON/OFF

(Good example) CSB terminal is pulled up to Vcc.

At power OFF, take 10ms or more before supply. If power is turned on without observing this condition, the IC

internal circuit may not be reset.

(Bad example) CSB terminal is “L” at power ON/OFF.

In this case, CSB always becomes “L” (active status), and EEPROM may have malfunction or erroneous write owing

to noises and the likes.

Even when CSB input is High-Z, the status becomes like this case.

○Operating timing after power ON

As shown in Fig.55, at standby, when SCK is “H”, even if CSB is fallen, SI status is not read at fall edge. SI status is read

at SCK rise edge after fall of CSB. At standby and at power ON/OFF, set CSB “H” status.

Even if CSB is fallen at SCK=”H”,

SI status is not read at that edge.

CSB

Command start here. SI is read.

SCK

0

1

2

SI

Fig.55 Operating timing

○At power on malfunction preventing function

This IC has a POR (Power On Reset) circuit as mistake write countermeasure. After POR action, it gets in write disable

status. The POR circuit is valid only when power is ON, and does not work when power is OFF. When power is ON, if the

recommended conditions of the following tR, tOFF, and Vbot are not satisfied, it may become write enable status owing to

noises and the likes.

tR

Vcc

Recommended conditions of t_R, t_OFF, Vbot

tR

tOFF

Vbot

tOFF

10ms or below

100ms or below

10ms or higher

0.3V or below

0.2V or below

Vbot

0

Fig.56 Rise waveform

○Low voltage malfunction preventing function

LVCC (Vcc-Lockout) circuit prevents data rewrite action at low power, and prevents wrong write.

At LVCC voltage (Typ. =1.2V) or below, it prevent data rewrite.

www.rohm.com

2010.12 - Rev.B

14/18

Technical Note

BR25S□□□Series

●Noise countermeasures

○Vcc noise (bypass capacitor)

When noise or surge gets in the power source line, malfunction may occur, therefore, for removing these, it is

recommended to attach a bypass capacitor (0.1μF) between IC Vcc and GND. At that time, attach it as close to IC as

possible.

And, it is also recommended to attach a bypass capacitor between board Vcc and GND.

○SCK noise

When the rise time of SCK (tRC) is long, and a certain degree or more of noise exists, malfunction may occur owing to

clock bit displacement. To avoid this, a Schmitt trigger circuit is built in SCK input. The hysteresis width of this circuit is set

about 0.2V, if noises exist at SCK input, set the noise amplitude 0.2Vp-p or below. And it is recommended to set the rise

time of SCK (tRC) 100ns or below. In the case when the rise time is 100ns or higher, take sufficient noise

countermeasures. Make the clock rise, fall time as small as possible.

○WPB noise

During execution of write status register command, if there exist noises on WPB pin, mistake in recognition may occur

and forcible cancellation may result. To avoid this, a Schmitt trigger circuit is built in WPB input. In the same manner, a

Schmitt trigger circuit is built in CSB input, SI input and HOLDB input too.

●Notes for use

(1) Described numeric values and data are design representative values, and the values are not guaranteed.

(2) We believe that application circuit examples are recommendable, however, in actual use, confirm characteristics further

sufficiently. In the case of use by changing the fixed number of external parts, make your decision with sufficient margin in

consideration of static characteristics and transition characteristics and fluctuations of external parts and our LSI.

(3) Absolute maximum ratings

If the absolute maximum ratings such as impressed voltage and operating temperature range and so forth are exceeded,

LSI may be destructed. Do not impress voltage and temperature exceeding the absolute maximum ratings. In the case of

fear exceeding the absolute maximum ratings, take physical safety countermeasures such as fuses, and see to it that

conditions exceeding the absolute maximum ratings should not be impressed to LSI.

(4) GND electric potential

Set the voltage of GND terminal lowest at any action condition. Make sure that each terminal voltage is higher than that

of GND terminal.

(5) Heat design

In consideration of permissible dissipation in actual use condition, carry out heat design with sufficient margin.

(6) Terminal to terminal short circuit and wrong packaging

When to package LSI onto a board, pay sufficient attention to LSI direction and displacement. Wrong packaging may

destruct LSI. And in the case of short circuit between LSI terminals and terminals and power source, terminal and GND

owing to foreign matter, LSI may be destructed.

(7) Use in a strong electromagnetic field may cause malfunction, therefore, evaluate design sufficiently.

www.rohm.com

2010.12 - Rev.B

15/18

Technical Note

BR25S□□□Series

●Ordering part number

B R

2 5

S

2

5

6

F

V

T - W

E

2

Part No.

BUS Type

25：SPI

Operating

temperature

range

Capacity

Package

F:SOP8

W-Cell

Packaging and

forming specification

320=32K

640=64K

FJ:SOP-J8

E2: Embossed

tape and reel

TR: Embossed

tape and reel

S:-40℃~+85℃ 128=128K

FV:SSOP-B8

FVT:TSSOP-B8

FVM:MSOP8

FVJ:TSSOP-B8J

256=256K

NUX:VSON008X2030

●Package specifications

SOP8

5.0± 0.2

(MAX 5.35 include BURR)

Tape

Embossed carrier tape

2500pcs

+

−

6

°

4°

4

°

Quantity

8

7

6

5

E2

Direction

of feed

The direction is the 1pin of product is at the upper left when you hold

reel on the left hand and you pull out the tape on the right hand

(

)

1

2

3

4

0.595

+0.1

0.17

-

0.05

S

0.1

S

1.27

Direction of feed

1pin

0.42± 0.1

Reel

Order quantity needs to be multiple of the minimum quantity.

(Unit : mm)

∗

SOP-J8

4.9± 0.2

(MAX 5.25 include BURR)

Tape

Embossed carrier tape

+

6°

4°

−4°

Quantity

2500pcs

8

7

6

5

E2

Direction

of feed

The direction is the 1pin of product is at the upper left when you hold

reel on the left hand and you pull out the tape on the right hand

(

)

1

2

3

4

0.545

0.2± 0.1

S

1.27

0.42± 0.1

0.1

Direction of feed

1pin

S

Reel

(Unit : mm)

Order quantity needs to be multiple of the minimum quantity.

∗

www.rohm.com

2010.12 - Rev.B

16/18

Technical Note

BR25S□□□Series

●Package specifications (Continue)

SSOP-B8

3.0± 0.2

Tape

Embossed carrier tape

2500pcs

(MAX 3.35 include BURR)

Quantity

8

7 6

5

E2

Direction

of feed

The direction is the 1pin of product is at the upper left when you hold

reel on the left hand and you pull out the tape on the right hand

(

)

1

2 3

4

0.15± 0.1

S

0.1

0.22± 0.10

M

0.08

Direction of feed

1pin

(0.52)

0.65

Reel

(Unit : mm)

Order quantity needs to be multiple of the minimum quantity.

∗

TSSOP-B8

3.0± 0.1

(MAX 3.35 include BURR)

Tape

Embossed carrier tape

4 ± ±4

8

7

6

5

Quantity

3000pcs

E2

Direction

of feed

The direction is the 1pin of product is at the upper left when you hold

reel on the left hand and you pull out the tape on the right hand

(

)

1

2

3

4

1PIN MARK

+0.05

0.145

−0.03

0.525

S

0.08 S

+0.05

0.245

M

−0.04

0.08

Direction of feed

1pin

0.65

Reel

(Unit : mm)

Order quantity needs to be multiple of the minimum quantity.

∗

TSSOP-B8J

3.0± 0.1

(MAX 3.35 include BURR)

4 ± ±4

Tape

Embossed carrier tape

8

7

6

5

Quantity

2500pcs

E2

Direction

of feed

The direction is the 1pin of product is at the upper left when you hold

reel on the left hand and you pull out the tape on the right hand

(

)

1

2

3

4

1PIN MARK

+0.05

0.525

0.145

−0.03

S

0.08

S

+0.05

0.32

−0.04

Direction of feed

1pin

M

0.08

0.65

Reel

(Unit : mm)

Order quantity needs to be multiple of the minimum quantity.

∗

www.rohm.com

2010.12 - Rev.B

17/18

Technical Note

BR25S□□□Series

●Package specifications (Continue)

MSOP8

2.9± 0.1

Tape

Embossed carrier tape

3000pcs

(MAX 3.25 include BURR)

+

6°

4°

Quantity

−4°

8

7

6

5

TR

Direction

of feed

The direction is the 1pin of product is at the upper right when you hold

reel on the left hand and you pull out the tape on the right hand

(

)

1

2

3

4

1PIN MARK

+0.05

1pin

+0.05

−0.03

0.145

0.475

S

0.22

−0.04

0.08

S

Direction of feed

Order quantity needs to be multiple of the minimum quantity.

0.65

Reel

(Unit : mm)

∗

VSON008X2030

2.0± 0.1

Tape

Embossed carrier tape

Quantity

4000pcs

TR

1PIN MARK

Direction

of feed

S

The direction is the 1pin of product is at the upper right when you hold

reel on the left hand and you pull out the tape on the right hand

(

)

0.08

S

1.5± 0.1

0.5

C0.25

1

4

8

5

0.25

Direction of feed

1pin

+0.05

−0.04

0.25

Reel

Order quantity needs to be multiple of the minimum quantity.

∗

(Unit : mm)

www.rohm.com

2010.12 - Rev.B

18/18

Notice

N o t e s

No copying or reproduction of this document, in part or in whole, is permitted without the

consent of ROHM Co.,Ltd.

The content speciﬁed herein is subject to change for improvement without notice.

The content speciﬁed herein is for the purpose of introducing ROHM's products (hereinafter

"Products"). If you wish to use any such Product, please be sure to refer to the speciﬁcations,

which can be obtained from ROHM upon request.

Examples of application circuits, circuit constants and any other information contained herein

illustrate the standard usage and operations of the Products. The peripheral conditions must

be taken into account when designing circuits for mass production.

Great care was taken in ensuring the accuracy of the information speciﬁed in this document.

However, should you incur any damage arising from any inaccuracy or misprint of such

information, ROHM shall bear no responsibility for such damage.

The technical information speciﬁed herein is intended only to show the typical functions of and

examples of application circuits for the Products. ROHM does not grant you, explicitly or

implicitly, any license to use or exercise intellectual property or other rights held by ROHM and

other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the

use of such technical information.

The Products speciﬁed in this document are intended to be used with general-use electronic

equipment or devices (such as audio visual equipment, ofﬁce-automation equipment, commu-

nication devices, electronic appliances and amusement devices).

The Products speciﬁed in this document are not designed to be radiation tolerant.

While ROHM always makes efforts to enhance the quality and reliability of its Products, a

Product may fail or malfunction for a variety of reasons.

Please be sure to implement in your equipment using the Products safety measures to guard

against the possibility of physical injury, ﬁre or any other damage caused in the event of the

failure of any Product, such as derating, redundancy, ﬁre control and fail-safe designs. ROHM

shall bear no responsibility whatsoever for your use of any Product outside of the prescribed

scope or not in accordance with the instruction manual.

The Products are not designed or manufactured to be used with any equipment, device or

system which requires an extremely high level of reliability the failure or malfunction of which

may result in a direct threat to human life or create a risk of human injury (such as a medical

instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, fuel-

controller or other safety device). ROHM shall bear no responsibility in any way for use of any

of the Products for the above special purposes. If a Product is intended to be used for any

such special purpose, please contact a ROHM sales representative before purchasing.

If you intend to export or ship overseas any Product or technology speciﬁed herein that may

be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to

obtain a license or permit under the Law.

Thank you for your accessing to ROHM product informations.

More detail product informations and catalogs are available, please contact us.

ROHM Customer Support System

http://www.rohm.com/contact/

www.rohm.com

R1010

A


型号：	BR25S256F-W
厂家：	ROHM
描述：	High speed clock action up to 20MHz(Max.), Wait function by HOLDB terminal.
文件：	总19页 (文件大小：600K)
中文：	中文翻译
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