10/16

BR25L010-W, BR25L020-W, BR25L040-W, BR25L080-W, BR25L160-W, BR25L320-W, BR25L640-W

Technical Note

At standby

WP cancel valid area

Fig.45 Operating timing

Fig.46 WP valid timing (WRSR)

Fig.47 WP valid timing (WRITE)

CS

SCK

SI

Command start here. SI is read.

Even if CS is fallen at SCL = SI = "H",

SI status is not read at that edge.

01

2

Ope code

Address

Data

tE/W

data write time

WP cancel invalid area

WP cancel invalid area

valid

invalid

invalid

WP cancel invalid area

Ope code

Data

tE/W

data write time

WP cancel invalid area

WP cancel invalid area

WP cancel invalid area

CS

SCK

15

16

WP is normally fixed to "H" or "L" for use, but when WP is controlled so as to cancel write status register command and write

command, pay attention to the following WP valid timing.

While write or write status register command is executed, by setting WP = "L" in cancel valid area, command can be

cancelled. The area from command ope code before CS rise at internal automatic write start becomes the cancel valid area.

However, once write is started, any input cannot be cancelled. WP input becomes Don't Care, and cancellation becomes

invalid.

By HOLD pin, command communication can be stopped temporarily. (HOLD status) The HOLD pin carries out command

communications normally when it is HIGH. To get in HOLD status, at command communication, when SCK = LOW, set

the HOLD 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 HOLD 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, leave CS LOW. When it is set

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

HOLD pin

Current at standby

Set CS "H", and be sure to set SCK, SI, WP, HOLD input "L" or "H". Do not input intermediate electric potential.

Timing

As shown in Fig. 45, at standby, when SCK is "H", even if CS is fallen, SI status is not read at fall edge. SI status is read

at SCK rise edge after fall of CS. At standby and at power ON/OFF, set CS "H" status.

2010.07 -

Rev. B

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