Analog and digital electronic thermometer with LM35

Electronic thermometer has countless applications. Not everywhere can we use the standard mercury thermometer, for example, due to its size, frailty or the need to measure from the distance. The advantage of electronic thermometers are also small size and heat capacity of probes, faster response of the digital display and elimination
Analog and digital electronic thermometer with LM35 - schematic

of toxic mercury. Its output also can be used to electronically processed, record the measured temperature, alarm when temperature is changing or work as a thermostat. circuit LM35: To build an electronic thermometer, i used LM35 integrated circuit, linear temperature sensor in TO92 - 3 pin housing that provides voltage proportional to temperature in degrees Celsius on its output. Conversion of the output voltage is 10mV / °C and can therefore be used directly to display on the digital meter. As the display, ordinary multimeter or digital panel meter can be used. The thermometer can also be built into the multimeter. If matter that the displayed value has to be divided by 10, can be panel the meter or multimeter tightly associated with the meter modified to move the decimal point. If we build thermometer as a removable extension of multimeter, you can use a resistive divider, and thereby obtain transfer 1mV / °C and display in °C. With a conventional multimeter, which has a range of 200mV to 0. 1 mV resolution, we get a thermometer with a resolution of 0. 1 °C. LM35 can be used in addition to building an analog thermometer with analog meter. I have added the circuit suppression capacitors 100n, because when using thermometer near EMI generation electronics there were deviations of up to 10 °C. The thermometer I use, among other things to measure the temperature of heatsinks and switching power converters, and so it was not...

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