8. case 06 NTC

8.1. Introduction


  • The temperature sensor is a sensor that can sense the temperature and convert the temperature to output signal. The temperature sensor is core of temperature measurement instrument.

8.2. Hardware Connect


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  • Connect circuit as above picture and put 2 AAA batteries into batteries pack.

8.3. Principles of Circuits


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  • The GND of slot on micro:bit is into innards of batteries’ GND to generate current loop.

8.4. Introduction of Components


NTC

  • The NTC is an analog temperature sensor where the output voltage and temperature form a liner relationship. The higher the temperature, the larger the output voltage.

  • The experiment box included a NTC.

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- Note: Please note the positive and the negative when you are connecting.

8.5. Software


Step 1

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Step 2

  • Reduction Formula:

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  • The reading is an analog value of the IO port, we need a formula as above to convert the values into Celsius.

Step 3

  • Set “Temperature” as a variable to store the Celsius.

  • As above formula, convert the values of P0 into Celsius.

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  • Show the temperature value and pauce a second.

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Program

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8.6. Result


  • Show the current temperature on the micro:bit allay.

8.7. Think


8.8. Questions


8.9. More Information