- 您現在的位置：買賣IC網 > Datasheet目錄39 > ADT7461AARMZ-R (ON Semiconductor)IC TEMP SENSOR DGTL 2CH 8-MSOP Datasheet資料下載
參數資料
| 型號： | ADT7461AARMZ-R |
| 廠商： | ON Semiconductor |
| 文件頁數： | 16/19頁 |
| 文件大小： | 294K |
| 描述： | IC TEMP SENSOR DGTL 2CH 8-MSOP |
| 產品變化通告： | MFG CHG Notification ADI to ON Semi |
| 標準包裝： | 3,000 |
| 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： | 0°C ~ 127°C，-55°C ~ 150°C |
| 精確度： | ±3°C |
| 拓撲： | ADC，比較器，多路復用器，寄存器庫 |
| 輸出類型： | 2 線 SMBus? |
| 輸出警報： | 是 |
| 輸出風扇： | 是 |
| 電源電壓： | 3 V ~ 5.5 V |
| 工作溫度： | -40°C ~ 120°C |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 8-TSSOP，8-MSOP（0.118"，3.00mm 寬） |
| 供應商設備封裝： | Micro8? |
| 包裝： | 帶卷 (TR) |
ADT7461A
http://onsemi.com
16
Figure 20. Operation of the THERM
and THERM2
Interrupts
THERM2
LIMIT
905C
805C
705C
605C
505C
405C
TEMPERATURE
1
2
3
4
THERM
305C
THERM
LIMIT
THERM2
" When the THERM2
limit is exceeded, the THERM2
signal asserts low.
" If the temperature continues to increase and exceeds the
THERM
limit, the THERM
output asserts low.
" The THERM
output deasserts (goes high) when the
temperature falls to THERM
limit minus hysteresis. In
Figure 20, there is no hysteresis value shown.
" As the system cools further, and the temperature falls
below the THERM2
limit, the THERM2
signal resets.
Again, no hysteresis value is shown for THERM2
.
Both the external and internal temperature measurements
cause THERM
and THERM2
to operate as described.
Application Information
Noise Filtering
For temperature sensors operating in noisy environments,
the industry standard practice was to place a capacitor across
the D+ and D pins to help combat the effects of noise.
However, large capacitances affect the accuracy of the
temperature measurement, leading to a recommended
maximum capacitor value of 1000 pF. Although this
capacitor reduces the noise, it does not eliminate it, making
it difficult to use the sensor in a very noisy environment.
The ADT7461A has a major advantage over other devices
when it comes to eliminating the effects of noise on the
external sensor. The series resistance cancellation feature
allows a filter to be constructed between the external
temperature sensor and the part. The effect of any filter
resistance seen in series with the remote sensor is
automatically cancelled from the temperature result.
The construction of a filter allows the ADT7461A and the
remote temperature sensor to operate in noisy environments.
Figure 21 shows a low-pass RCR filter, where R = 100 W
and C = 1 nF. This filtering reduces both common-mode and
differential noise.
Figure 21. Filter Between Remote Sensor and
ADT7461A Factors Affecting Diode Accuracy
100 W
100 W
1 nF
D+
D
REMOTE
TEMPERATURE
SENSOR
Remote Sensing Diode
The ADT7461A is designed to work with substrate
transistors built into processors or with discrete transistors.
Substrate transistors are generally PNP types with the
collector connected to the substrate. Discrete types are either
PNP or NPN transistors connected as diodes (base-shorted
to collector). If an NPN transistor is used, the collector and
base are connected to D+ and the emitter to D. If a PNP
transistor is used, the collector and base are connected to D
and the emitter to D+.
To reduce the error due to variations in both substrate and
discrete transistors, consider several factors:
" The ideality factor, nF, of the transistor is a measure of
the deviation of the thermal diode from ideal behavior.
The ADT7461A is trimmed for an nF value of 1.008.
The following equation may be used to calculate the
error introduced at a temperature, T (癈), when using a
transistor whose nF does not equal 1.008. Consult the
processor data sheet for the nF values.
DT + (nF * 1.008)1.008 (273.15 Kelvin ) T) (eq. 1)
To factor this in, the user writes the DT value to the offset
register. It is then automatically added to, or subtracted
from, the temperature measurement.
" Some CPU manufacturers specify the high and low
current levels of the substrate transistors. The high
current level of the ADT7461A, I
HIGH
, is 220 mA and
the low level current, I
LOW
, is 13.5 mA. If the
ADT7461A current levels do not match the current
levels specified by the CPU manufacturer, it may
become necessary to remove an offset. The CPU data
sheet should advise whether this offset needs to be
removed and how to calculate it. This offset is
programmed to the offset register. It is important to
note that if more than one offset must be considered,
the algebraic sum of these offsets must be programmed
to the offset register.
If a discrete transistor is used with the ADT7461A, the
best accuracy is obtained by choosing devices according to
the following criteria:
" Base-emitter voltage greater than 0.25 V at 6 mA, at the
highest operating temperature
相關PDF資料 |
PDF描述 |
|---|---|
| ADT7461ARMZ-2R | IC TEMP SENSOR DGTL 2CH 8-MSOP |
| ADT7463ARQZ-REEL | IC REMOTE THERMAL CTRLR 24-QSOP |
| ADT7476AARQZ-R | IC REMOTE THERMAL CTLR 24QSOP |
| ADT7481ARMZ-1RL | IC SENSOR TEMP 2CH ALARM 10MSOP |
| ADT7482ARMZ-REEL | IC SENSOR TEMP 2CH ALARM 10MSOP |
相關代理商/技術參數 |
參數描述 |
|---|---|
| ADT7461AARMZ-REEL | 功能描述:IC SENSOR TEMP DGTL 2CH 8-MSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 熱管理 系列:- 標準包裝:1 系列:- 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:-40°C ~ 125°C，外部傳感器 精確度:±2.5°C 本地（最大值），±5°C 遠程（最大值） 拓撲:ADC，比較器，寄存器庫 輸出類型:2 線 SMBus? 輸出警報:無 輸出風扇:無 電源電壓:2.7 V ~ 5.5 V 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-8 供應商設備封裝:SOT-23-8 包裝:Digi-Reel® 其它名稱:296-22675-6 |
| ADT7461AARMZ-REEL7 | 功能描述:IC SENSOR TEMP DGTL 2CH 8-MSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 熱管理 系列:- 標準包裝:1 系列:- 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:-40°C ~ 125°C，外部傳感器 精確度:±2.5°C 本地（最大值），±5°C 遠程（最大值） 拓撲:ADC，比較器，寄存器庫 輸出類型:2 線 SMBus? 輸出警報:無 輸出風扇:無 電源電壓:2.7 V ~ 5.5 V 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-8 供應商設備封裝:SOT-23-8 包裝:Digi-Reel® 其它名稱:296-22675-6 |
| ADT7461AARMZ-RL7 | 功能描述:板上安裝溫度傳感器 1 TMP DIO MON W/SMBUS ITF 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 |
| ADT7461AEBZEVB | 功能描述:BOARD EVAL FOR ADT7461 RoHS:是 類別:編程器，開發系統 >> 過時/停產零件編號 系列:- 標準包裝:1 系列:- 傳感器類型:CMOS 成像，彩色（RGB） 傳感范圍:WVGA 接口:I²C 靈敏度:60 fps 電源電壓:5.7 V ~ 6.3 V 嵌入式:否 已供物品:成像器板 已用 IC / 零件:KAC-00401 相關產品:4H2099-ND - SENSOR IMAGE WVGA COLOR 48-PQFP4H2094-ND - SENSOR IMAGE WVGA MONO 48-PQFP |
| ADT7461AR | 功能描述:IC TEMP MONITOR +/-1C DUAL 8SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 熱管理 系列:- 標準包裝:1 系列:- 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:-40°C ~ 125°C，外部傳感器 精確度:±2.5°C 本地（最大值），±5°C 遠程（最大值） 拓撲:ADC，比較器，寄存器庫 輸出類型:2 線 SMBus? 輸出警報:無 輸出風扇:無 電源電壓:2.7 V ~ 5.5 V 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-8 供應商設備封裝:SOT-23-8 包裝:Digi-Reel® 其它名稱:296-22675-6 |
發布緊急采購，3分鐘左右您將得到回復。