Why Does an NTC Thermistor Suppress Surge Current?
From lianglite • Electronics Classroom
Many switching power supplies, LED drivers, and home appliances are highly vulnerable to component damage from inrush current surges at power-on. Power-type NTC thermistors are core protection devices specially designed to suppress startup surge impacts.
Core Characteristics
The lower the temperature, the higher the resistance;
the higher the temperature, the lower the resistance.
Working Principle
At the moment of power-on, the NTC thermistor has a low temperature and high resistance, effectively limiting the instantaneous large inrush current and preventing surge damage to the circuit.
After the device operates normally, the NTC heats up and its resistance drops rapidly, resulting in minimal power loss without affecting stable equipment performance.
In short: limits current for surge protection at startup, and runs with low power consumption “invisibly” during normal operation. With low cost and excellent protection performance, it has become a standard current-limiting component for switching power supplies, adapters, and LED driver power supplies.
LiangLite specializes in a full range of circuit protection components including MOV varistors, TMOV thermal-protected varistors, NTC thermistors, and SPD surge protection devices. With complete specifications and stable performance, we provide reliable and efficient surge protection solutions for various power supplies and electronic equipment.