1. Types & Physical Appearance

Thermistor

Small cylindrical package (1-5mm diameter), epoxy/glass coating

Thermocouple

Metal probe with two dissimilar metal wires

RTD (Pt100)

Stainless steel housing with platinum element

2. Internal Structure & Operation

Thermistor Structure

Semiconductor ceramic core with silver electrodes

Thermocouple Working Principle

Seebeck effect diagram showing voltage generation

3. Typical Circuit Configurations

+5V
  |
  |---Fixed Resistor---|
  |              |
  |---NTC Thermistor---|
                   |
                    Vout
  |
GND

DS18B20
  |
  |--VDD (3-5V)
  |--DQ (Data with 4.7kΩ pull-up)
  |--GND

4. Industrial & Daily Life Applications

Factory automation temperature monitoring

Infrared forehead thermometer

Smart thermostat in home automation