The role of NTC and the phenomenon of abnormalities
2023.8.22
Articles
GOTREND Technology Co.,Ltd
NTC (Negative Temperature Coefficient), also known as thermistors, as the temperature increases the resistance decreases exponentially, with a negative temperature coefficient thermistor phenomenon and material.
NTC thermistors are semiconductor ceramics made of two or more metal oxides such as manganese (Mn), copper(Cu), silicon(Si), cobalt(Co), nickel(Ni), and zinc(Zn) for adequate mixing, molding, and sintering.
GOTREND Products are mainly used in wireless charging coils and their modules, and different forms of NTC thermistors and applications can be seen.
Let's learn more about what is the role of NTC thermistors in GOTREND products ? In addition, if an abnormality occurs, how to quickly judge and what phenomenon will occur?
1、 What does a NTC thermistor do?
NTC thermistor is widely used in switching power supply, module power supply, temperature sensor, power supply, electronic rectifier, automatic regulation heating, circuit protection and other places, its small size, large power, used in the power supply circuit when the main operation to suppress the inrush current (also known as surge current) , generally in series in the input circuit, it has a rated zero power resistance value, when connected in series in a power loop, the inrush current at startup can be effectively suppressed and the power consumption is almost negligible.
Usually when the switching power supply is turned on, there will be a high peak inrush current to charge the filter capacitor, thereby charging the device. These inrush currents can affect the life of the capacitor and damage the contacts of the power switch to damage the rectifier diode, so thermistors are the best solution.
So what is the application and role of NTC thermistors in GOTREND products?
GOTREND's products are primarily utilized in wireless charging coils and their modules. Their main function is to provide temperature protection against overcharging for chargers, and to act as over-temperature protection when components within the module generate heat or encounter foreign objects during charging. Furthermore, during the moment when the power supply is connected in the charger circuit, the circuit generates a surge current that is several times higher than normal operational levels, also known as Inrush Current.
The initial resistance value of the NTC thermistor is relatively high, which helps suppress excessive currents in the circuit, thereby safeguarding the power supply circuit and the load.
NTC thermistors are semiconductor ceramics made of two or more metal oxides such as manganese (Mn), copper(Cu), silicon(Si), cobalt(Co), nickel(Ni), and zinc(Zn) for adequate mixing, molding, and sintering.
GOTREND Products are mainly used in wireless charging coils and their modules, and different forms of NTC thermistors and applications can be seen.
Let's learn more about what is the role of NTC thermistors in GOTREND products ? In addition, if an abnormality occurs, how to quickly judge and what phenomenon will occur?
1、 What does a NTC thermistor do?
NTC thermistor is widely used in switching power supply, module power supply, temperature sensor, power supply, electronic rectifier, automatic regulation heating, circuit protection and other places, its small size, large power, used in the power supply circuit when the main operation to suppress the inrush current (also known as surge current) , generally in series in the input circuit, it has a rated zero power resistance value, when connected in series in a power loop, the inrush current at startup can be effectively suppressed and the power consumption is almost negligible.
Usually when the switching power supply is turned on, there will be a high peak inrush current to charge the filter capacitor, thereby charging the device. These inrush currents can affect the life of the capacitor and damage the contacts of the power switch to damage the rectifier diode, so thermistors are the best solution.
So what is the application and role of NTC thermistors in GOTREND products?
GOTREND's products are primarily utilized in wireless charging coils and their modules. Their main function is to provide temperature protection against overcharging for chargers, and to act as over-temperature protection when components within the module generate heat or encounter foreign objects during charging. Furthermore, during the moment when the power supply is connected in the charger circuit, the circuit generates a surge current that is several times higher than normal operational levels, also known as Inrush Current.
The initial resistance value of the NTC thermistor is relatively high, which helps suppress excessive currents in the circuit, thereby safeguarding the power supply circuit and the load.
2、What is the phenomenon when NTC is abnormal?
NTC thermistors belong to a category of sensitive components, how does it behave when using NTC thermistors to fail?
From GOTREND's experience in using NTC thermal resistors, there are three main types :
(1) NTC thermistor short-circuit/open-circuit
In an NTC thermistor circuit, when the circuit current is higher than the standard value, or the rated power is higher than the resistance for a long time, the temperature of the thermistor is higher than the set value, and all at the time of current start-up, the thermistor will exhibit a fairly low resistance, and then the thermistor will be burned, resulting in an open circuit or short circuit.
(2) NTC thermistor cracking
When the circuit current begins to operate, it may cause instantaneous large energy to be loaded into the thermistor, if the NTC thermistor has defects in the process or process during production, then the NTC thermistor may not be able to withstand and then damage, in general, the NTC thermistor will show high resistance or direct cracking.
(3) NTC thermistor value offset
NTC thermistor is a thermally sensitive semiconductor component, if IR reflow soldering, wave soldering, and other soldering, or rework, baking, etc.
Exceed a certain temperature and time, the thermistor is also easy to damage, resulting in resistance deviation, the resistance of the NTC thermistor under this anomaly may become larger or smaller.
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