With the advancement of technology, electronic products have become essential in our daily lives. Think about it: items like lights, computers, and smartphones are indispensable for lighting, communication, and office work.
As these devices operate, current flows through their circuits, generating heat. Some devices have strict temperature requirements; if the temperature exceeds a certain range, the device’s performance can degrade or even be damaged. For example, a computer CPU overheating may cause the system to crash or restart, and precision instruments may yield inaccurate measurements.
This is where thermistors, components sensitive to temperature changes, come into play. A thermistor is a type of semiconductor component whose resistance varies with temperature.
Thermistors offer advantages like high temperature sensitivity, wide operating temperature range, small size, easy processing, and fast response time, making them widely used in temperature measurement and control applications.
Thermistors are classified into two types based on their temperature coefficient:
PTC (Positive Temperature Coefficient) thermistors, whose resistance increases as temperature rises.
NTC (Negative Temperature Coefficient) thermistors, whose resistance decreases as temperature rises.
To measure the resistance of a thermistor at a specific temperature, a multimeter is typically used. Here’s how to do it:
1. Set Up the Multimeter
Thermistors have a wide range of resistance values, so it’s best to start by setting the multimeter to the highest range. If the reading is too small, it means the range is too large, and you can adjust it to a smaller range for more accurate readings.
2. Connect the Multimeter and Read the Value
Connect the multimeter’s red and black probes to the thermistor’s two leads. Note that thermistors are non-polarized, meaning the probes can be connected in any direction.
Once connected, the multimeter will display a resistance value, which is the thermistor’s resistance at the current temperature.
Important Tip:
To get an accurate measurement, ensure the thermistor is in a constant temperature state. Temperature fluctuations can cause errors in the resistance readings, so try to avoid any environmental changes during the measurement process.
This article is provided by JYH HSU (JEC) Electronics. JEC is a research, development, production, and sales-oriented company specializing in manufacturing and selling various electronic components such as capacitors and resistors.
Post time: Oct-29-2025