BR25H640F-2LB Datasheet, PDF (14/31 Pages) Rohm – Serial EEPROM Series Industrial EEPROM 125℃ Operation SPI BUS EEPROM

BR25H640F-2LB
Datasheet
Features
○Status registers
This IC has status registers. The status registers are of 8 bits and express the following parameters.
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.
Number of data rewrite times 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 command.
Status registers
Product number
bit 7
bit 6 bit 5 bit 4 bit 3
bit 2
bit 1
bit 0
BR25H640F-2LB WPEN 0
0
0
BP1
BP0
WEN
――
R /B
bit
Memory
location
WPEN EEPROM
BP1
BP0
EEPROM
WEN Register
――
R /B
Register
Function
WPB pin enable / disable designation bit
WPEN=0=invalid , WPEN=1=valid
EEPROM write disable block designation bit
Write and write status register write enable
/ disable status confirmation bit
WEN=0=prohibited , WEN=1=permitted
Write cycle status (READY / BUSY) confirmation bit
R/B=0=READY , R/B=1=BUSY
Contents
This enables / disables the functions of WPB pin.
This designates the write disable area of
EEPROM. Write designation areas of product
numbers are shown below.
This confirms prohibited status or permitted
status of the write and the write status register.
This confirms READY status or BUSY status of
the write cycle.
Write disable block setting
BP1 BP0
BR25H640F-2LB
0
0
0
1
1
0
1
1
None
1800h-1FFFh
1000h-1FFFh
0000h-1FFFh
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©2013 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
14/28
TSZ02201-0R1R0G100360-1-2
27.Feb.2014 Rev.002