Temperature Digital Output
Binary Hex
−25°C 1110 0111 0000 0000 E700h
−55°C 1100 1001 0000 0000 C900h
11-bit, unsigned binary
Temperature Digital Output
Binary Hex
+255.875°C 1111 1111 1110 0000 FFE0h
+255°C 1111 1111 0000 0000 FF00h
+201°C 1100 1001 0000 0000 C900h
+125°C 0111 1101 0000 0000 7D00h
+25°C 0001 1001 0000 0000 1900h
+1°C 0000 0001 0000 0000 0100h
+0.125°C 0000 0000 0010 0000 0020h
0°C 0000 0000 0000 0000 0000h
When the digital filter is enabled on Remote 1 and 2 channels
temperature data is represented by a 13-bit unsigned binary
or 12-bit plus sign (two's complement) word with an LSb equal
to 0.03125°C.
13-bit, 2's complement (12-bit plus sign)
Temperature Digital Output
Binary Hex
+125°C 0111 1101 0000 0000 7D00h
+25°C 0001 1001 0000 0000 1900h
+1°C 0000 0001 0000 0000 0100h
+0.03125°C 0000 0000 0000 1000 0008h
0°C 0000 0000 0000 0000 0000h
−0.03125°C 1111 1111 1111 1000 FFF8h
−1°C 1111 1111 0000 0000 FF00h
−25°C 1110 0111 0000 0000 E700h
−55°C 1100 1001 0000 0000 C900h
13-bit, unsigned binary
Temperature Digital Output
Binary Hex
+255.875°C 1111 1111 1110 0000 FFE0h
+255°C 1111 1111 0000 0000 FF00h
+201°C 1100 1001 0000 0000 C900h
+125°C 0111 1101 0000 0000 7D00h
+25°C 0001 1001 0000 0000 1900h
+1°C 0000 0001 0000 0000 0100h
+0.03125°C 0000 0000 0000 1000 0008h
0°C 0000 0000 0000 0000 0000h
Local Temperature data is only represented by an 11-bit,
two's complement, word with an LSb equal to 0.125°C.
11-bit, 2's complement (10-bit plus sign)
Temperature Digital Output
Binary Hex
+125°C 0111 1101 0000 0000 7D00h
+25°C 0001 1001 0000 0000 1900h
Temperature Digital Output
Binary Hex
+1°C 0000 0001 0000 0000 0100h
+0.125°C 0000 0000 0010 0000 0020h
0°C 0000 0000 0000 0000 0000h
−0.125°C 1111 1111 1110 0000 FFE0h
−1°C 1111 1111 0000 0000 FF00h
−25°C 1110 0111 0000 0000 E700h
−55°C 1100 1001 0000 0000 C900h
1.7 SMBDAT OPEN-DRAIN OUTPUT
The SMBDAT output is an open-drain output and does not
have internal pull-ups. A “high” level will not be observed on
this pin until pull-up current is provided by some external
source, typically a pull-up resistor. Choice of resistor value
depends on many system factors but, in general, the pull-up
resistor should be as large as possible without effecting the
SMBus desired data rate. This will minimize any internal tem-
perature reading errors due to internal heating of the
LM95213. The maximum resistance of the pull-up to provide
a 2.1V high level, based on LM95213 specification for High
Level Output Current with the supply voltage at 3.0V, is 82
kΩ (5%) or 88.7 kΩ (1%).
1.8 TCRIT1, TCRIT2, AND TCRIT3 OUTPUTS
The LM95213's TCRIT pins are active-low open-drain outputs
and do not include internal pull-up resistors. A “high” level will
not be observed on these pins until pull-up current is provided
by some external source, typically a pull-up resistor. Choice
of resistor value depends on many system factors but, in gen-
eral, the pull-up resistor should be as large as possible without
effecting the performance of the device receiving the signal.
This will minimize any internal temperature reading errors due
to internal heating of the LM95213. The maximum resistance
of the pull-up to provide a 2.1V high level, based on LM95213
specification for High Level Output Current with the supply
voltage at 3.0V, is 82 kΩ (5%) or 88.7 kΩ (1%). The three
TCRIT pins can each sink 6 mA of current and still guarantee
a "Logic Low" output voltage of 0.4V. If all three pins are set
at maximum current this will cause a power dissipation of 7.2
mW. This power dissipation combined with a thermal resis-
tance of 77.8°C/W will cause the LM95213's junction temper-
ature to rise approximately 0.6°C and thus cause the Local
temperature reading to shift. This can only be cancelled out if
the environment that the LM95213 is enclosed in has stable
and controlled air flow over the LM95213, as airflow can
cause the thermal resistance to change dramatically.
1.9 TCRIT LIMITS AND TCRIT OUTPUTS
Figure 4 describes a simplified diagram of the temperature
comparison and status register logic. Figure 5 describes a
simplified logic diagram of the circuitry associated with the
status registers, mask registers and the TCRIT output pins.
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LM95213