Datasheet

Technical Note
4/18
BR25S□□□ Series
www.rohm.com
2010.12 - Rev.B
© 2010 ROHM Co., Ltd. All rights reserved.
●Pin assignment and description
Terminal
name
Input
/Output
Function
Vcc - Power source to be connected
GND - All input / output reference voltage, 0V
CSB Input Chip select input
SCK Input Serial clock input
SI Input Start bit, ope code, address, and serial data input
SO Output Serial data output
HOLDB Input
Hold input
Command communications may be suspended temporarily
(HOLD status)
WPB Input
Write protect input
Write command is prohibited
Write status register command is prohibited
●Sync data input / output timing
●AC timing characteristics conditions
Parameter Symbol
Limits
Unit
Min. Typ. Max.
Load capacity C
L
- - 30 pF
Input rise time - - - 50 ns
Input fall time - - - 50 ns
Input voltage - 0.2Vcc/0.8Vcc V
Input / Output judgment voltage - 0.3Vcc/0.7Vcc V
●Characteristic data (The following characteristic data are Typ. Values.)
Vcc
HOLDB
SCK SI
CSB SO WPB GND
BR25S320-W
BR25S640-W
BR25S128-W
BR25S256-W
Fig.2 Pin assignment diagram
Fig.3 Input timing
CSB
SCK
SI
SO
tCS
tCSS
tSCKS
tSCKWL
tSCKWH
tDIS
tDIH
tRC
tFC
High-Z
SI is taken into IC inside in sync with data rise edge of
SCK. Input address and data from the most significant bit
MSB
Fig.4 Input / Output timing
CSB
SCK
SI
SO
tPD
tOH
tRO,tFO
tOZ
tCSH
tSCKH
tCS
Hi
g
h-Z
Fig.5 HOLD timing
CSB
SCK
SI
n+1
"H"
"L"
n
Dn
n-1
Dn Dn-1
HOLDB
SO
Dn+1
tHFS tHFH
tHOZ
tHRS tHRH
tDIS
tHPD
High-Z
SO is output in sync with data fall edge of SCK. Data is
output from the most significant bit MSB.
0
0.2
0.4
0.6
0.8
1
0123456
IOL[mA]
VOL1[V]
Ta=-40℃
Ta=25℃
Ta=85℃
SPEC
Fig.8 "L" output voltage VOL1 (Vcc=2.5V)
0
1
2
3
4
5
6
0123456
Vcc[V]
VIH[V]
SPEC
Ta=-40℃
Ta=25℃
Ta=85℃
Fig.6 "H" input voltage VIH(CSB,SCK,SI,HOLDB,WPB)
0
1
2
3
4
5
6
0123456
Vcc[V]
VIL[V]
SPEC
Ta=-40℃
Ta=25℃
Ta=85℃
Fig.7 "L" input voltage VIL(CSB,SCK,SI,HOLDB,WPB)