Thermistor ppt presentation.By the student from PSG College of technology.the student name is G.prasanna. the teacher handle the student name was L.Ashok kumar. Electrical and electronics department.

1. THERMISTOR
-21T212

2. THERMISTOR
A thermistor (or thermal resistor) is defined as a type of
resistor whose electrical resistance varies with changes in
temperature. Although all resistors’ resistance will fluctuate
slightly with temperature, a thermistor is particularly
sensitive to temperature changes.

3. WORKING PRINCIPLE OF THERMISTOR
• The working principle of a thermistor is that its resistance is dependent on its
temperature. We can measure the resistance of a thermistor using an ohmmeter.
• If we know the exact relationship between how changes in the temperature will
affect the resistance of the thermistor – then by measuring the thermistor’s
resistance we can derive its temperature.
• The relationship between a thermistor’s temperature and resistance is non-linear.

4. TYPES OF THERMISTOR
• There are two types of thermistors:
1. Negative Temperature Coefficient (NTC) Thermistor
2. Positive Temperature Coefficient (PTC) Thermistor

5. USES OF THERMISTOR
Thermistors have a variety of applications. They are widely used as a way to measure temperature as
a thermistor thermometer in many different liquid and ambient air environments. Some of the most
common uses of thermistors include:
• Digital thermometers (thermostats)
• Automotive applications (to measure oil and coolant temperatures in cars & trucks)
• Household appliances (like microwaves, fridges, and ovens)

6. ADVANTAGES OF THERMISTOR
• They are more sensitive than other temperature sensors.
• High sensitivity allows them to work well over a small temperature range.
• They’re low cost and therefore cheap to replace.
• They provide a fast response.
• Easy to use.

7. DISADVANTAGES OF THERMISTOR
• Not easily interchangeable.
• High resistance, noise problems.
• Non linear.
• Unstable due to drift and decalibration (especially at high temperatures)
• Narrow span.
• Fragile.