NTC thermistor is a temperature sensitive electronic component whose resistance value is significantly reduced with increasing temperature. NTC thermistors are mainly made of semiconductor materials, such as oxide mixtures, whose electrical resistivity is highly sensitive to temperature.

working principle

The working principle of NTC thermistors is based on the thermoelectric effect of materials. In NTC thermistors, as the temperature increases, the carrier concentration of the semiconductor increases, leading to a decrease in resistance value. The characteristic of negative temperature coefficient makes NTC thermistors very suitable for temperature measurement and temperature compensation.

characteristic

Negative Temperature Coefficient: The resistance value of NTC thermistors decreases with increasing temperature, which is consistent with the name "Negative Temperature Coefficient" in its name.

High sensitivity: Compared to other temperature sensors such as platinum resistance temperature detectors (RTDs), NTC thermistors have a more sensitive response to temperature changes.

Cost effectiveness: NTC thermistors are usually cheaper than other types of temperature sensors, making them an economical choice in many applications.

Size diversity: NTC thermistors come in a variety of sizes and shapes to choose from, from small SMT to large axial lead type.

Quick response: Due to its small size, NTC thermistors can quickly respond to temperature changes.

application

NTC thermistors are widely used in various fields, including but not limited to:

Temperature measurement: used for precise temperature measurement in fields such as automobiles, medical equipment, and household appliances.

Temperature compensation: Used in electronic circuits to compensate for performance changes caused by temperature changes.

Overheat protection: Used as an overheating protection device in power supplies, motors, and other equipment.

Surge current limitation: Used in power circuits to limit the surge current during startup.

Packaging size: NTC thermistors come in a variety of packaging sizes to meet different application requirements and installation conditions. Package dimensions are usually expressed in English units, such as inches, or in metric units, such as millimeters. Here are some common NTC thermistor assemblies

Installation dimensions and their corresponding metric and imperial dimensions:

0402 (1005): The length is 0.04 inches (1.0mm) and the width is 0.02 inches (0.5mm).

0603 (1608): The length is 0.06 inches (1.6mm) and the width is 0.03 inches (0.8mm).

0805 (2012): The length is 0.08 inches (2.0mm) and the width is 0.05 inches (1.25mm).

1206 (3216): The length is 0.12 inches (3.2mm) and the width is 0.06 inches (1.6mm).

1210 (3225): The length is 0.12 inches (3.2mm) and the width is 0.10 inches (2.5mm).

2010 (5025): Length is 0.20 inches (5.0mm), width is 0.10 inches (2.5mm).

2512 (6332): The length is 0.25 inches (6.3mm) and the width is 0.12 inches (3.2mm).

In addition to the common SMD packaging sizes mentioned above, NTC thermistors also come in other types of packaging, such as:

Axial Led Package: This type of packaging for NTC thermistors typically has two slender leads, suitable for traditional plug-in circuit boards (Through Hole PCBs).

Radial Leaded Package: Leads extend from both sides of the component, suitable for compact installation space.

Glass Enclosed: This type of NTC thermistor packaging has better corrosion resistance and mechanical strength, making it suitable for harsh environments.

When selecting NTC thermistors, in addition to considering packaging size, factors such as resistance value, B value (material constant), accuracy, temperature range, response time, etc. should also be considered to ensure that specific application requirements are met. In addition, the installation method can also affect the selection of packaging size. For example, if surface mounting is carried out on an automated production line, it is necessary to choose SMT packaging that is suitable for the SMT process.

NTC thermistors are powerful and flexible temperature sensing elements that play an important role in modern electronic products. By selecting and applying NTC thermistors correctly, they can help improve the performance and reliability of products.