BR24G32-3A ROHM [Rohm], BR24G32-3A Datasheet - Page 20

• Manufacturer Part Number: BR24G32-3A
• Description: High Reliability Serial EEPROMs I2C BUS BR24xxxxfamily
• Manufacturer: ROHM [Rohm]

●I/O peripheral circuit
noise margin 0.1Vcc.
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© 2012 ROHM Co., Ltd. All rights reserved.
BR24G32-3A
TSZ22111・15・001
○Pull up resistance of SDA terminal
○Maximum value of R
○ Minimum value of R
○Pull up resistance of SCL terminal
SDA is NMOS open drain, so requires pull up resistance. As for this resistance value (R
this resistance value from microcontroller V
limited. The smaller the R
The maximum value of R
①SDA rise time to be determined by the capacitance (CBUS) of bus line of R
And AC timing should be satisfied even when SDA rise time is late.
②The bus electric potential A to be determined by input leak total (I
SDA bus and R
recommended noise margin 0.2Vcc.
The minimum value of R
When IC outputs LOW, it should be satisfied that V
When SCL control is made at CMOS output port, there is no need, but in the case there is timing where SCL becomes
'Hi-Z', add a pull up resistance. As for the pull up resistance, one of several kΩ to several ten kΩ is recommended in
consideration of drive performance of output port of microcontroller.
VCC－ILRPU－0.2 VCC ≧ VIH
②VOLMAX=0.4V should secure the input 'L' level (V
from②
from ①
R
PU
Ex.) VCC =3V IL=10μA VIH=0.7 VCC
Ex.) VCC =3V, VOL=0.4V, IOL=3mA, microcontroller, EEPROM V
∴
∴
≦
≦
And
R
PU
Therefore, the condition ② is satisfied.
V
VOLMAX ≦ VIL－0.1 VCC
0.8×3－0.7×3
R
R
30 ［kΩ］
CC－
PU
PU
R
PU
PU
10×10
PU
≧
≧ 867 ［Ω］
PU
should sufficiently secure the input 'H' level (V
V
≧
PU
OL
≦
PU
PU
3－0.4
, the larger the consumption current at action.
3×10
-6
≦
VOL=0.4［V］
V
is determined by the following factors.
VIL=0.3×3
0.8V
is determined by the following factors.
CC－
I
I
OL
OL
-3
CC－
V
=0.9［V］
I
L
OL
V
IH
IL
, I
L
, and V
OLMAX
OL
20/34
-I
=0.4V and I
OL
IL
characteristics of this IC. If R
) of microcontroller and EEPROM including recommended
Microcontroller
OLMAX
L
IH
=3mA.
) of device connected to bus at output of 'H' to
) of microcontroller and EEPROM including
I
L
IL
Fig.45 I/O circuit diagram
PU
=0.3Vcc
and SDA should be tR or below.
TSZ02201-0R2R0G100050 -1-2
PU
R
PU
), select an appropriate value to
Bus line
capacity
CBUS
PU
A
is large, action frequency is
I
L
15.May.2012 REV.001
BR24GXX
SDA
terminal
Datasheet
Datasheet