This feature makes them ideal for use in countless applications. There are many different semiconducting thermistors with a range from about 0. In ptc thermistors, the resistance increases as temperature increases. These are made of semiconductor compounds such as sulphides,oxides,silicates of. Thermistors can provide velocity measurements in response to changes in heat transfer, which for a given geometry is principally a function of the air speed and temperature. Ntc thermistors ntcg seriessmd, pb free ntcg06101620 types ntcnegative temperature coefficient thermistors are manufactured from sintered metal oxides. Ntc thermistors can detect the ambient temperature for different purposes, depending on the battery system. Thermistors arent the only devices that measure temperature. A thermistor is a type of resistor whose resistance is dependent on temperature, more so than in standard resistors. What is thermistor types of thermistor, advantages and. Before going in to the details of what is a sensor, what are the different types of sensors and applications of these different types of sensors, we will first take a look at a simple example of an. Thermistors, derived from the term thermaily sensitive resistors, are a very accurate and cost effective sensor for measuring temperature.
Thermistors are part of our temperature range of products. By using the concept discussed in this section, its possible to design and fabricate different types of thermistors with ntcs and ptcs. With an ntc thermistor, when the temperature increases, resistance decreases. Ptc thermistors, general technical information tdk electronics. Types of thermistors, characteristic details and working. Rtds are useful over larger temperature ranges, while thermistors typically achieve a. These heatdependent resistors can operate in one of two ways, either by increasing or decreasing their resistive value with changes in temperature. There are mainly 2 types of thermistors namely positivetemperature coefficient ptc and negativetemperature coefficient ntc. We are all known that a resistor is an electrical component that limits the amount of current flows through a circuit. Different types of resistors and its color code calculation in electronics resistors are the most commonly used components in electronic circuits and devices. Types and applications thermistors are ceramic semiconductors. Negative temperature coefficient ntc and positive temperature coefficient ptc. Thermistors are mostly used in digital thermometers and household appliances, such. A resistor whose resistance changes significantly with a change in temperature.
Now that we have discussed about the types of thermistors according to the type of temperature coefficient, there is another classification based on the shape and size of the thermistors. Thermistors can be used to sense temperatures in a reliable, cheap costeffective, and simple manner. The figure below shows some of the different commercial forms. Ntc thermistors, application notes tdk electronics. The different models of ptc thermistors from epcos are equally diverse, offering the matching. A thermistor is an inexpensive and easily obtainable temperature sensitive resistor, thermistor working principle is, its resistance depends upon the temperature.
Thermistor basics, working principle, types and applications. On the other hand, the temperature coefficient of thermistor is considerably high, thus their resistance change with respect to change in. All of the bead type thermistors have platinum alloy. This value indicates the resistance value at a temperature of 25 o c. Ntc thermistor temperature sensors are temperature sensing devices made from sintered semiconducting ceramic material that contains a mix of several metal oxides. The resistance, r, provides the required reduction in. Ptc thermistors are classified based on the temperature level they measure. If you contact us via email, well always respond within one business day. There are different types of thermistors which suit different. Thermistors vs thermocouples, resistance thermometers, and varistors. Measurement error caused by selfheating in ntc and ptc.
Like the rtd, the thermistor is also a temperature. By combining different oxides, thermistors can have different sintering temperatures and. Ntc thermistors description through traditional craftsmanship and engineering excellence, the zettler name has symbolized quality and reliability in electrical components for over 100 years in demanding. Although all resistors resistance will fluctuate slightly. Thermistors can be in the form of discs, beads, rods etc.
Thermistor definition a resistor whose resistance changes significantly with a change in temperature. A thermistor or thermal resistor is defined as a type of resistor whose electrical resistance varies with changes in temperature. Each bead type thermistor has a platinum alloy lead wire connected directly to the ceramic body. Thermistors are semiconductor resistance thermometer used to measure the temperature. How to select an ntc thermistor thermistors ametherm. Conversely, when temperature decreases, resistance increases. Thermistors types and applications thermistor principle. Ptc thermistors increase their resistance as the temperature rises. When the temperature of the thermistor is low, its. These are of disk, plate and cylinder types of thermistors. Beyond the range of the positive temperature coefficient. The second group uses metalized surface contacts, which offer leads, radial leads, axial, or no lead for surface mounting.
The most common package is a disk, although they are also available with axial leads and can be purchased as chip or metal electrode leadless faces. Thermistors and ntc thermistors basic electronics tutorials. Manual on the use of thermocouples in temperature measurement. The different types of the thermistor are shown in the figure below. Thermistors are widely used as inrush current limiters, temperature sensors negative temperature coefficient or ntc type typically, selfresetting overcurrent protectors, and selfregulating heating elements positive. The applications in which the thermistors can be used are of a wide range. Specifications are typical and may not apply to all applications. As shown in the figure, a bridge circuit is also used so as to increase the thermistors sensitivity. The first group of ntc thermistors is denoted by bead type thermistors. Thermistors are easy to use, inexpensive, sturdy and respond predictably to a change in temperature. Ntc thermistors, on the other hand, are used as currentlimiters and temperature monitors in digital thermostats. Common oxides used in creating ntc thermistors are cobalt, titanium, copper, and even manganese.
Types of resistors the two main characteristics of a resistor are its resistance, r, in ohms and its power rating, p, in watts. A thermistor is a type of resistor whose resistance is dependent on temperature, more so than. Commercially available thermistors have nominal values of 1k, 2k, 10k, 20k, 100k, etc. This page compares thermocouple vs rtd vs thermistor and mentions difference between thermocouple,rtd and thermistor w. Thermistors a thermistor is another special type of resistor. Thermistors types and applications electronics hub. Applications utilizing the influence of ambient temperature on resistance. Ametherm prides itself on being an innovative and responsive manufacturer.
The different models of ptc thermistors from epcos are equally diverse. The bead form of the thermistor is smallest in shape, and it is enclosed inside the solid glass rod to form probes. Thermistors are available in several package types. These have high temperature coatings for mechanical protection, environmental stability and electrical insulation. The wide range of different ntc thermistors by analog. Other types may be seen but generally they follow a similar approach typically using the old resistor symbol of a zigzag line as the basis with the same line through it as used with the more conventional. Thermistor is a word formed by combining thermal with resistor. Thermistors are classified into two types based on how they behave with the change in temperature.