- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄385490 > LM95241 (National Semiconductor Corporation) Dual Remote Diode Temperature Sensor with SMBus Interface and TruTherm⑩ Technology (65nm/90nm) PDF資料下載
參數(shù)資料
| 型號： | LM95241 |
| 廠商： | National Semiconductor Corporation |
| 元件分類： | 溫度/濕度傳感器 |
| 英文描述： | Dual Remote Diode Temperature Sensor with SMBus Interface and TruTherm⑩ Technology (65nm/90nm) |
| 中文描述： | 雙遠程二極管溫度傳感器，帶有SMBus接口和TruTherm⑩科技（65nm/90nm） |
| 文件頁數(shù)： | 17/19頁 |
| 文件大?。?/td> | 708K |
| 代理商： | LM95241 |
3.0 Applications Hints
(Continued)
TruTherm should only be enabled when measuring the tem-
perature of a transistor integrated as shown in the processor
of
Figure 3
, because
Equation (5)
only applies to this topol-
ogy.
3.1.2 Calculating Total System Accuracy
The voltage seen by the LM95241 also includes the I
F
R
S
voltage drop of the series resistance. The non-ideality factor,
η
, is the only other parameter not accounted for and de-
pends on the diode that is used for measurement. Since
V
BE
is proportional to both
η
and T, the variations in
η
cannot be distinguished from variations in temperature.
Since the non-ideality factor is not controlled by the tempera-
ture sensor, it will directly add to the inaccuracy of the
sensor. For the Pentium D processor on 65nm process, Intel
specifies a +4.06%/0.89% variation in
η
from part to part
when the processor diode is measured by a circuit that
assumes diode equation,
Equation (4)
, as true. As an ex-
ample, assume a temperature sensor has an accuracy
specification of
±
1.25C at a temperature of 65 C (338
Kelvin) and the processor diode has a non-ideality variation
of +4.06%/0.89%. The resulting system accuracy of the
processor temperature being sensed will be:
T
ACC
= + 1.25C + (+4.06% of 338 K) = +14.97 C
and
T
ACC
= - 1.25C + (0.89% of 338 K) = 4.26 C
TrueTherm technology uses the transistor equation,
Equa-
tion (5)
, resulting in a non-ideality spread that truly reflects
the process variation which is very small. The transistor
equation non-ideality spread is
±
0.4% for the Pentium D
processor on 65nm process. The resulting accuracy when
using TruTherm technology improves to:
T
ACC
=
±
1.25C + (
±
0.4% of 338 K) =
±
2.60 C
The next error term to be discussed is that due to the series
resistance of the thermal diode and printed circuit board
traces. The thermal diode series resistance is specified on
most processor data sheets. For the Pentium D processor
on 65 nm process, this is specified at 4.52
typical. The
LM95241 accommodates the typical series resistance of the
Pentium D processor on 65nm process. The error that is not
accounted for is the spread of the Pentium’s series resis-
tance, that is 2.79
to 6.24
or
±
1.73
. The equation to
calculate the temperature error due to series resistance
(T
ER
) for the LM95241 is simply:
(6)
Solving
Equation (6)
for R
equal to
±
1.73
results in the
additional error due to the spread in the series resistance of
±
1.07C. The spread in error cannot be canceled out, as it
would require measuring each individual thermal diode de-
vice. This is quite difficult and impractical in a large volume
production environment.
Equation (6)
can also be used to calculate the additional
error caused by series resistance on the printed circuit
board. Since the variation of the PCB series resistance is
minimal, the bulk of the error term is always positive and can
simply be cancelled out by subtracting it from the output
readings of the LM95241.
Processor Family
Intel processor on
65nm process
Transistor Equation
n
D
, non-ideality
min
typ
0.997
1.001
Series
R
max
1.005
4.52
Processor Family
Diode Equation
η
D
,
non-ideality
min
typ
1
1.0065 1.0125
1.0057
1.008
Series
R
max
Pentium III CPUID 67h
Pentium III CPUID
68h/PGA370Socket/
Celeron
Pentium 4, 423 pin
Pentium 4, 478 pin
Pentium 4 on 0.13
micron process,
2-3.06GHz
Pentium 4 on 90 nm
process
Pentium on 65 nm
porcess
Pentium M Processor
(Centrino)
MMBT3904
AMD Athlon MP model
6
AMD Athlon 64
AMD Opteron
1.0125
0.9933 1.0045 1.0368
0.9933 1.0045 1.0368
1.0011 1.0021 1.0030 3.64
1.0083
1.011
1.023
3.33
1.000
1.009
1.050
4.52
1.001511.002201.00289 3.06
1.003
1.008
1.002
1.016
1.008
1.008
1.008
1.008
1.096
1.096
20199743
FIGURE 3. Thermal Diode Current Paths
L
www.national.com
17
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LM95241CIMM | Dual Remote Diode Temperature Sensor with SMBus Interface and TruTherm⑩ Technology (65nm/90nm) |
| LM95241CIMM-1 | Dual Remote Diode Temperature Sensor with SMBus Interface and TruTherm⑩ Technology (65nm/90nm) |
| LM95241CIMM-2 | Dual Remote Diode Temperature Sensor with SMBus Interface and TruTherm⑩ Technology (65nm/90nm) |
| LM95241CIMMX | Dual Remote Diode Temperature Sensor with SMBus Interface and TruTherm⑩ Technology (65nm/90nm) |
| LM95241CIMMX-1 | Dual Remote Diode Temperature Sensor with SMBus Interface and TruTherm⑩ Technology (65nm/90nm) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LM95241CIMM | 功能描述:板上安裝溫度傳感器 RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 1.5 C, +/- 3 C 溫度閾值: 數(shù)字輸出 - 總線接口:2-Wire, I2C, SMBus 電源電壓-最大:5.5 V 電源電壓-最小:4.5 V 最大工作溫度:+ 50 C 最小工作溫度:0 C 關(guān)閉: 安裝風(fēng)格: 封裝 / 箱體: 設(shè)備功能:Temperature and Humidity Sensor |
| LM95241CIMM/NOPB | 功能描述:板上安裝溫度傳感器 RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 1.5 C, +/- 3 C 溫度閾值: 數(shù)字輸出 - 總線接口:2-Wire, I2C, SMBus 電源電壓-最大:5.5 V 電源電壓-最小:4.5 V 最大工作溫度:+ 50 C 最小工作溫度:0 C 關(guān)閉: 安裝風(fēng)格: 封裝 / 箱體: 設(shè)備功能:Temperature and Humidity Sensor |
| LM95241CIMM-1 | 功能描述:板上安裝溫度傳感器 RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 1.5 C, +/- 3 C 溫度閾值: 數(shù)字輸出 - 總線接口:2-Wire, I2C, SMBus 電源電壓-最大:5.5 V 電源電壓-最小:4.5 V 最大工作溫度:+ 50 C 最小工作溫度:0 C 關(guān)閉: 安裝風(fēng)格: 封裝 / 箱體: 設(shè)備功能:Temperature and Humidity Sensor |
| LM95241CIMM-1/NOPB | 功能描述:板上安裝溫度傳感器 RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 1.5 C, +/- 3 C 溫度閾值: 數(shù)字輸出 - 總線接口:2-Wire, I2C, SMBus 電源電壓-最大:5.5 V 電源電壓-最小:4.5 V 最大工作溫度:+ 50 C 最小工作溫度:0 C 關(guān)閉: 安裝風(fēng)格: 封裝 / 箱體: 設(shè)備功能:Temperature and Humidity Sensor |
| LM95241CIMM-2 | 功能描述:板上安裝溫度傳感器 RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 1.5 C, +/- 3 C 溫度閾值: 數(shù)字輸出 - 總線接口:2-Wire, I2C, SMBus 電源電壓-最大:5.5 V 電源電壓-最小:4.5 V 最大工作溫度:+ 50 C 最小工作溫度:0 C 關(guān)閉: 安裝風(fēng)格: 封裝 / 箱體: 設(shè)備功能:Temperature and Humidity Sensor |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。