- 您現在的位置：買賣IC網 > Datasheet目錄45 > NCT210RQR2G (ON Semiconductor)IC TEMP SENSOR LOC/REM 16QSOP Datasheet資料下載
參數資料
| 型號： | NCT210RQR2G |
| 廠商： | ON Semiconductor |
| 文件頁數： | 13/15頁 |
| 文件大?。?/td> | 184K |
| 描述： | IC TEMP SENSOR LOC/REM 16QSOP |
| 標準包裝： | 2,500 |
| 功能： | 溫度監控系統（傳感器） |
| 傳感器類型： | 內部和外部 |
| 感應溫度： | -65°C ~ 127°C |
| 精確度： | ±3°C 本地（最大），±5°C 遠程（最大） |
| 拓撲： | ADC（三角積分型），比較器，寄存器庫 |
| 輸出類型： | 2 線 SMBus? |
| 輸出警報： | 是 |
| 輸出風扇： | 無 |
| 電源電壓： | 3 V ~ 5.5 V |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 16-SSOP（0.154"，3.90mm 寬） |
| 供應商設備封裝： | 16-QSOP |
| 包裝： | 帶卷 (TR) |
NCT210
http://onsemi.com
13
obtained by choosing devices according to the following
criteria:
1. Base-emitter voltage greater than 0.25 V at 6 mA,
at the highest operating temperature.
2. Base-emitter voltage less than 0.95 V at 100 mA, at
the lowest operating temperature.
3. Base resistance less than 100 W.
4. Small variation in h
FE
(such as 50 to 150), which
indicates tight control of V
BE
characteristics.
Transistors, such as 2N3904, 2N3906, or equivalents, in
SOT23 package are suitable devices to use.
Thermal Inertia and Self-heating
Accuracy depends on the temperature of the
remote-sensing diode and/or the internal temperature sensor
being at the same temperature as that being measured, and a
number of factors can affect this. Ideally, the sensor should be
in good thermal contact with the part of the system being
measured, for example the processor. If it is not, the thermal
inertia caused by the mass of the sensor causes a lag in the
response of the sensor to a temperature change. For the
remote sensor, this should not be a problem, because it is
either a substrate transistor in the processor or a small package
device, such as SOT23, placed in close proximity to it.
The on-chip sensor is, however, often remote from the
processor and only monitors the general ambient
temperature around the package. The thermal time constant
of the QSOP16 package is approximately 10 seconds.
In practice, the package will have an electrical, and hence
a thermal, connection to the printed circuit board, so the
temperature rise due to self-heating is negligible.
Layout Considerations
Digital boards can be electrically noisy environments, and
because the NCT210 is measuring very small voltages from
the remote sensor, care must be taken to minimize noise
induced at the sensor inputs. The following precautions
should be taken:
1. Place the NCT210 as close as possible to the
remote sensing diode. Provided that the worst
noise sources, such as clock generators,
data/address buses, and CRTs, are avoided, this
distance can be four to eight inches.
2. Route the D+ and D tracks close together, in
parallel, with grounded guard tracks on each side.
Provide a ground plane under the tracks, if
possible.
3. Use wide tracks to minimize inductance and
reduce noise pickup. 10 mil track minimum width
and spacing is recommended.
4. Try to minimize the number of copper/solder
joints, which can cause thermocouple effects.
Where copper/solder joints are used, ensure they
are in both the D+ and D paths and at the same
temperature.
Thermocouple effects should not be a major
problem as 1癈 corresponds to about 240 mV, and
thermocouple voltages are about 3 mV/癈 of
temperature difference. Unless there are two
thermocouples with a big temperature differential
between them, thermocouple voltages should be
much less than 240 mV.
5. Place a 0.1 mF bypass capacitor close to the V
DD
pin, and 2,200 pF input filter capacitors across D+,
D close to the NCT210.
6. If the distance to the remote sensor is more than
eight inches, the use of twisted pair cable is
recommended. This works up to about 6 to 12 feet.
7. For very long distances (up to 100 feet), use
shielded twisted pair, such as Belden #8451
microphone cable. Connect the twisted pair to D+
and D and the shield to GND close to the
NCT210. Leave the remote end of the shield
unconnected to avoid ground loops.
Figure 17. Arrangement of Signal Tracks
10 MIL
10 MIL
10 MIL
10 MIL
10 MIL
10 MIL
10 MIL
GND
D
D+
GND
Because the measurement technique uses switched
current sources, excessive cable and/or filter capacitance
can affect the measurement. When using long cables, the
filter capacitor can be reduced or removed. Cable resistance
can also introduce errors. A series resistance of 1 W
introduces about 1癈 error.
Application Circuits
Figure 18 shows a typical application circuit for the
NCT210, using a discrete sensor transistor connected via a
shielded, twisted pair cable. The pullups on SCLK, SDATA,
and ALERT
are required only if they are not already
provided elsewhere in the system.
The SCLK and SDATA pins of the NCT210 can be
interfaced directly to the SMBus of an I/O chip. Figure 19
shows how the NCT210 might be integrated into a system
using this type of I/O controller.
相關PDF資料 |
PDF描述 |
|---|---|
| NCT214MT3R2G | IC TEMP SENSOR LOC/REM 10WDFN |
| NCT72CMNR2G | IC REMOTE THERMAL SENSOR 8-DFN |
| NCT7491RQR2G | IC REMOTE THERMAL MONITOR 24QSOP |
| NCT75MNR2G | IC SENSOR TEMP DGTL 8DFN |
| NCV8881PWR2G | IC REG TRPL BUCK/LINEAR 16SOIC |
相關代理商/技術參數 |
參數描述 |
|---|---|
| NCT214MT3R2G | 功能描述:板上安裝溫度傳感器 TEMP SENS W MULTIPLE ADD 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 關閉: 安裝風格: 封裝 / 箱體: 設備功能:Temperature and Humidity Sensor |
| NCT218FCT2G | 制造商:ON Semiconductor 功能描述:NCT218 CSP OPN - Tape and Reel 制造商:ON Semiconductor 功能描述:REEL / NCT218 CSP OPN 制造商:ON Semiconductor 功能描述:BATTERY PWR |
| NCT218MTR2G | 制造商:ON Semiconductor 功能描述:LOW VOLTAGE LOCAL TEMPERA - Tape and Reel 制造商:ON Semiconductor 功能描述:REEL / LOW VOLTAGE LOCAL TEMPERA 制造商:ON Semiconductor 功能描述:Low Voltage, High Accuracy Temperature Monitor with I2C Interface |
| NCT22/D | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Low Cost Single Trip Point Temperature Sensor |
| NCT22DR2 | 制造商:Rochester Electronics LLC 功能描述:- Bulk 制造商:ON Semiconductor 功能描述: |
發布緊急采購，3分鐘左右您將得到回復。