摘要
本文研制的无触点型电子温控器,全部选用集成电路,其温度传感器则选用SWF9热敏电阻。开停温差系用运算放大器来控制。时基电路NE555用来控制光电耦合器MOC3022,光电耦合器依次触发三端双向可控硅。将电压的变化,转变为温度的变化,是因电压与电阻成正比,并通过-增益可调的直流放大器来放大,因此输出电压能精确地反映温度在数值上的变化。然后通过3(1/2) A/D转换器7107和共阳极LED实现温度显示。
The developed noncontacting electronic temperature controller is completely composed of integrated circuits with SWF9 thermister as its sensor of temperature. On-off temperature difference is controlled by an operational amplifier. And time-base circuit NE555 is used to control a photocoupler MOC3022, which in turn triggers a triple-ended bidirectional diode thyristor. The change of voltage to the temperature, which is propotional to that of the resistance, is amplified by a DC amplifier with adjustable gain, so that the output voltage exactly equals to the temperature change in value. On using a 3 1/2-bit A/D converter 7170 and a common-anode LED, the temperature is digitally displayed.
出处
《河北工学院学报》
1991年第3期51-56,共6页
Journal of Hubei Polytechnic University
关键词
电冰箱
温控器
IC
数字显示
无触点
Noncontacting
Electronic temperature controller
Temperaturesensor
Thermistor
On-off temperature difference
Operational amplifier
photocoupler
Triple-ended bidirectionai diode thyristor
DC amplifier
Common-anode LED
