.

PTC Thermistor Working Principle

PTC thermistor (Positive Temperature Coefficient Thermistor) is a temperature-sensitive semiconductor resistor. Once it exceeds a certain temperature (Curie temperature), its resistance value increases almost stepwise with the increase of temperature. The temperature change of the positive temperature coefficient thermistor can be obtained by the current flowing through the PTC thermistor, or by the external heat input or the combination of the two.

Ceramic materials are usually used as excellent insulators with high resistance. Ceramic PTC is made of barium titanate and doped with other polycrystalline ceramic materials, which has low resistance and semiconductivity. It is achieved by purposefully doping a material with higher chemical valence as the lattice element of the crystal: a part of barium ions or titanate ions in the crystal lattice is replaced by higher valence ions. Therefore, a certain number of free electrons are obtained.

Then, let's look at the reason for PTC thermistoreffect, in other words, the reason for the step increase in resistance value. The material structure is composed of many small crystallites, and the potential is formed on the grain boundary, which prevents the electrons from crossing the boundary into the adjacent area, thus resulting in high resistance. This effect is offset at low temperatures: the high dielectric constant and spontaneous polarization at the grain boundary hinder the formation of barriers and allow electrons to flow freely at low temperatures. At high temperatures, this effect greatly reduces the dielectric constant and polarization, leading to a substantial increase in the barrier and resistance, showing a strong PTC effect.

PTC is a kind of semiconductor heating ceramic. When the external temperature decreases, the resistance value of PTC decreases, and the calorific value increases correspondingly. PTC thermistor working principleis as follows: once it exceeds a certain temperature (Curie temperature), the resistance increases of positive temperature coefficient resistor with the increase of temperature almost in a step-by-step manner. The temperature change of PTC thermistor types body can be obtained by the current flowing through it, or by the external input heat or the combination of the two. Ceramic materials are usually used as excellent insulators with high resistance, PTC ceramics are based on barium titanate and doped with other polycrystalline ceramic materials, which have low resistance and semiconductivity. It is achieved by purposely doping a kind of material with higher chemical value as the lattice element of the crystal: in the lattice, part of barium ions or titanate ions are replaced by higher valence ions. Therefore, a certain number of free electrons are obtained.

As one of industrial sensor suppliers, we will do our best to meet all the needs of customers.



Send product request

To: Shenzhen Temp-sen sensor Co., LTD
Your E-mail:
Message text:


Send to other suppliers

Other supplier products

Pellet Grill Inside Temperature Sensor TPS200813-31
Pellet Grill Inside Temperature Sensor TPS200813-31 TPS24 type Microwave temperature sensoris a high level temperature sensor, very stable performance with very short response time, when you need to ...
PM1.0 PM2.5 PM10 Laser Particle Dust Sensor Digital Module
PM1.0 PM2.5 PM10 Laser Particle Dust Sensor Digital Module D7 is a kind of digital and universal particle temperature sensor, which can be used to obtain the number of suspended particles in the air,i.e.the...
Charging Pile Temperature Sensor TPS200724-11
Charging Pile Temperature Sensor TPS200724-11 Specification: TPS200724-11 Details Material: NTC glass-sealed thermistor / high-temperature Teflon wire / PVDF heat shrinkable film Applica...
Glass Bead Thermistor, Single-ended Glass-sealed Thermistor
Glass Bead Thermistor, Single-ended Glass-sealed Thermistor As one of the leading industrial sensor suppliers, TOPOSwas founded in 2003. In the beginning, it is the first company that can mass-produce the mo...
PM1.0 PM2.5 PM10 Laser Particle Dust Sensor Digital Module
PM1.0 PM2.5 PM10 Laser Particle Dust Sensor Digital Module D7 is a kind of digital and universal particle concentration sensor, which can be used to obtain the number of suspended particles in the air,i.e.t...
All supplier products

Same products

Hangzhi CAFR-A-NP Series PCB Current sensor
Hangzhi CAFR-A-NP Series PCB Current sensor Seller: Shenzhen Hangzhi Precision Electronics Co., Ltd The CAFR-A-NP series is a current sensor developed by Hangzhi that can be soldered on the PCB cir...
Hangzhi CIT High Precision Split Core current transducer
Hangzhi CIT High Precision Split Core current transducer Seller: Shenzhen Hangzhi Precision Electronics Co., Ltd The CIT series high precision split core current transducer is developed by Hangzhi based on the ...
BMS300 Automotive Current Sensor Transducer
BMS300 Automotive Current Sensor Transducer Seller: Shenzhen Hangzhi Precision Electronics Co., Ltd BMS300 fluxgate transducer is made of an excitation magnetic ring and a control circuit. Under no...
AIT6000-SG High-Precision Current Sensor Transducer, Accuracy 50ppm
AIT6000-SG High-Precision Current Sensor Transducer, Accuracy 50ppm Seller: Shenzhen Hangzhi Precision Electronics Co., Ltd AIT6000-SG has a high gain and measurement accuracy in the full bandwidth range, due to the appli...
DIT300-SG high-precision digital current sensor
DIT300-SG high-precision digital current sensor Seller: Shenzhen Hangzhi Precision Electronics Co., Ltd Hangzhi DIT300-SG is a 300 Amp High Precision Digital Current Transducer with an accuracy of 200p...