Datasheet
SMBus
Master
* Place close to LM95231 pins.
** Optional may be required in noisy systems; place close to LM95231 pins.
Q1
MMBT3904
LM95231
1
2
3
4
D1+
D1-
D2+
D2-
5
6
7
8
V
DD
SMBCLK
SMBDAT
GND
C1*
100 pF
C2
0.1 PF
SMBCLK
SMBDAT
C4**
100 pF
Pentium
®
4
PROCESSOR
C5**
100 pF
+3.3V
Standby
R1
1.3k
R2
1.3k
C3
10 PF
+
LM95231
V
DD
SMBCLK
SMBDAT
D1+
D1-
D2+
D2-
1
2
3
4 5
6
7
8
GND
LM95231
SNIS139E –FEBRUARY 2005–REVISED MARCH 2013
www.ti.com
Connection Diagram
Figure 1. VSSOP-8
TOP VIEW
Typical Application
PIN DESCRIPTIONS
Label Pin # Function Typical Connection
D1+ 1 Diode Current Source To Diode Anode. Connected to remote discrete diode-
connected transistor junction or to the diode-connected
transistor junction on a remote IC whose die temperature is
being sensed. A capacitor is not required between D1+ and
D1-. A 100 pF capacitor between D1+ and D1− can be added
and may improve performance in noisy systems.
D1− 2 Diode Return Current Sink To Diode Cathode. A capacitor is not required between D1+
and D1-. A 100 pF capacitor between D1+ and D1− can be
added and may improve performance in noisy systems.
D2+ 3 Diode Current Source To Diode Anode. Connected to remote discrete diode-
connected transistor junction or to the diode-connected
transistor junction on a remote IC whose die temperature is
being sensed. A capacitor is not required between D2+ and
D2-. A 100 pF capacitor between D2+ and D2− can be added
and may improve performance in noisy systems.
D2− 4 Diode Return Current Sink To Diode Cathode. A capacitor is not required between D2+
and D2-. A 100 pF capacitor between D2+ and D2− can be
added and may improve performance in noisy systems.
GND 5 Power Supply Ground System low noise ground
V
DD
6 Positive Supply Voltage Input DC Voltage from 3.0 V to 3.6 V. V
DD
should be bypassed with
a 0.1 µF capacitor in parallel with 100 pF. The 100 pF
capacitor should be placed as close as possible to the power
supply pin. Noise should be kept below 200 mVp-p, a 10 µF
capacitor may be required to achieve this.
SMBDAT 7 SMBus Bi-Directional Data Line, From and to Controller; may require an external pull-up resistor
Open-Drain Output
SMBCLK 8 SMBus Clock Input From Controller; may require an external pull-up resistor
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