參數(shù)資料
型號(hào)： TMP01EP
廠商： ANALOG DEVICES INC
元件分類： 溫度/濕度傳感器
英文描述： Low Power, Programmable Temperature Controller
中文描述： ANALOG TEMP SENSOR-VOLTAGE, 2.49-2.5V, RECTANGULAR, THROUGH HOLE MOUNT
封裝： MINI, PLASTIC, DIP-8
文件頁(yè)數(shù)： 13/16頁(yè)
文件大?。?/td> 377K
代理商： TMP01EP
TMP01
REV. C
–13–
4 mA-20 mA Current Loop
Another, very common method of transmitting a signal over
long distances is to use a 4 mA-20 mA Loop, as shown in Fig-
ure 19. An advantage of using a 4 mA-20 mA loop is that the
accuracy of a current loop is not compromised by voltage drops
across the line. One requirement of 4 mA-20 mA circuits is that
the remote end must receive all of its power from the loop,
meaning that the circuit must consume less than 4 mA. Operat-
ing from +5 V, the quiescent current of the T MP01 is 500
μ
A
max, and the OP90s is 20
μ
A max, totaling less than 4 mA.
Although not shown, the open collector outputs and tempera-
ture setting pins can be connected to do any local control of
switching.
T he current is proportional to the voltage on the VPT AT out-
put, and is calibrated to 4 mA at a temperature of –40
°
C, to
20 mA for +85
°
C. T he main equation governing the operation
of this circuit gives the current as a function of VPT AT :
I
OUT
=
1
R
6
VPTAT
×
R
5
R
2
±
VREF
×
R
3
R
3
+
R
1
1
+
R
5
R
2
T he resulting temperature coefficient of the output current is
128
μ
A/
°
C.
5
8
1
4
R
L
2N1711
VREF
GND
V+
VPTAT
TMP01
R5
100k
R2
39.2k
7
6
4
3
2
OP90
R1
243k
R3
100k
R6
100
4–20mA
+5V TO +13.2V
Figure 19. 4-20 mA Current Loop
T o determine the resistor values in this circuit, first note that
VREF remains constant over temperature. T hus the ratio of R5
over R2 must give a variation of I
OUT
from 4 mA to 20 mA as
VPT AT varies from 1.165 V at –40
°
C to 1.79 V at +85
°
C. T he
absolute value of the resistors is not important, only the ratio.
For convenience, 100 k
is chosen for R5. Once R2 is calcu-
lated, the value of R3 and R1 is determined by substituting
4 mA for I
OUT
and 1.165 V for VPT AT and solving. T he final
values are shown in the circuit. T he OP90 is chosen for this cir-
cuit because of its ability to operate on a single supply and its
high accuracy. For initial accuracy, a 10 k
trim potentiometer
can be included in series with R3, and the value of R3 lowered
to 95 k
. T he potentiometer should be adjusted to produce an
output current of 12.3 mA at 25
°
C.
T emperature-to-Frequency Converter
Another common method of transmitting analog information is
to convert a voltage to the frequency domain. T his is easily
done with any of the low cost monolithic Voltage-to-Frequency
Converters (VFCs) available, which feature a robust, open-col-
lector digital output. A digital signal is very immune to noise
and voltage drops because the only important information is the
frequency. As long as the conversions between temperature and
frequency are done accurately, the temperature data can be suc-
cessfully transmitted.
A simple circuit to do this combines the T MP01 with an
AD654 VFC, as shown in Figure 20. T he AD654 outputs a
square wave that is proportional to the dc input voltage accord-
ing to the following equation:
F
OUT
=
V
IN
10(
R
1
+
R
2)
C
T
By simply connecting the VPT AT output to the input of the
AD654, the 5 mV/
°
C temperature coefficient gives a sensitivity
of 25 Hz/
°
C, centered around 7.5 kHz at 25
°
C. T he trimming
resistor R2 is needed to calibrate the absolute accuracy of the
AD654. For more information on that part, please consult the
AD654 data sheet. Finally, the AD650 can be used to accu-
rately convert the frequency back to a dc voltage on the receiv-
ing end.
4
3
7
6
8
1
2
5
AD654
VPTAT
5
V+
R1
R2
R3
TEMPERATURE
SENSOR &
VOLTAGE
REFERENCE
1
2
3
4
HYSTERESIS
GENERATOR
WINDOW
COMPARATOR
TMP01
VPTAT
VREF
7
8
6
R1
1.8k
R2
500
OSC
V+
F
OUT
C
T
0.1
μ
F
5k
V+
Figure 20. Temperature-to-Frequency Converter
相關(guān)PDF資料
PDF描述
TMP01ES Low Power, Programmable Temperature Controller
TMP01FP Low Power, Programmable Temperature Controller
TMP01FS Low Power, Programmable Temperature Controller
TMP01GBC CONNECTOR ACCESSORY
TMP01FJ2 Low Power, Programmable Temperature Controller
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TMP01ES 功能描述:IC SENSOR TEMP/CONTROLLER 8SOIC RoHS:否 類別:傳感器，轉(zhuǎn)換器 >> 溫度 系列:- 其它有關(guān)文件:DS1820 Digital Thermometer 標(biāo)準(zhǔn)包裝:500 系列:- 感應(yīng)溫度:-55°C ~ 125°C 輸出類型:開路漏極 電源電壓:3 V ~ 5.5 V 精確度:±0.5°C 封裝/外殼:TO-226-3、TO-92-3 標(biāo)準(zhǔn)主體 供應(yīng)商設(shè)備封裝:TO-92 包裝:散裝
TMP01ES-REEL 功能描述:IC SENSOR TEMP/CONTROLLER 8SOIC RoHS:否 類別:傳感器，轉(zhuǎn)換器 >> 溫度 系列:- 其它有關(guān)文件:DS1820 Digital Thermometer 標(biāo)準(zhǔn)包裝:500 系列:- 感應(yīng)溫度:-55°C ~ 125°C 輸出類型:開路漏極 電源電壓:3 V ~ 5.5 V 精確度:±0.5°C 封裝/外殼:TO-226-3、TO-92-3 標(biāo)準(zhǔn)主體 供應(yīng)商設(shè)備封裝:TO-92 包裝:散裝
TMP01ESZ 功能描述:IC SENSOR TEMP/CONTROLLER 8SOIC RoHS:是 類別:傳感器，轉(zhuǎn)換器 >> 溫度 系列:- 其它有關(guān)文件:DS1820 Digital Thermometer 標(biāo)準(zhǔn)包裝:500 系列:- 感應(yīng)溫度:-55°C ~ 125°C 輸出類型:開路漏極 電源電壓:3 V ~ 5.5 V 精確度:±0.5°C 封裝/外殼:TO-226-3、TO-92-3 標(biāo)準(zhǔn)主體 供應(yīng)商設(shè)備封裝:TO-92 包裝:散裝
TMP01ESZ 制造商:Analog Devices 功能描述:IC, TEMPERATURE CONTROLLER 1.5C 8-SOIC
TMP01ESZ1 制造商:AD 制造商全稱:Analog Devices 功能描述:Low Power Programmable Temperature Controller
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*