¿Qué es un fusible de chips reiniciable??

A resettable chip fuse, also known as a PTC (Coeficiente de temperatura positiva) resettable fuse, is a type of surface mount device (SMD) that protects electronic circuits from overcurrent and overheating. It acts like a traditional fuse but can automatically reset itself after a fault is cleared. When a fault like an overcurrent or short circuit occurs, the fuse’s resistance increases, limiting the current flow. Once the fault is removed and the fuse cools down, its resistance returns to normal, permitiendo que la corriente vuelva a fluir.

PPTC chip self recovery fuse 1210 2A 2.5A 3A 6V 30V 33V 60V SMD

Resettable SMD Fuse 1206 SMD Chip 6V 0.35A (e0113 4c5f1 48d2a d4c5b 1f85e d0afa

Fusible SMD Resetable 1812 16V 2A Chip de montaje de superficie para protección contra sobrecorriente de comunicación

El fusible de chip reajustable (PPTC) Es un elemento de protección contra sobrecorriente basado en las características del coeficiente de temperatura positivo de un polímero.. Tiene una función de reinicio automático y se usa ampliamente en la protección de circuitos de equipos electrónicos.. Los siguientes son sus puntos centrales.:

1. Estructura y principio de funcionamiento.
‌Composición del material‌
It is composed of a specially treated polymer resin (such as PE polymer) y partículas conductoras (negro de carbón o partículas metálicas). En condiciones normales, las partículas conductoras forman un camino de baja resistencia (0.1-varios ohmios)‌.
‌Protection Mechanism‌
Cuando ocurre sobrecorriente, el efecto térmico de la corriente hace que la resina se derrita y se expanda, the conductive network breaks, and the resistance suddenly increases to a high resistance state (up to the megohm level), limiting the current to the microampere level‌.
After the fault is resolved, las partículas conductoras se enfrían y se encogen, reconectar, and return to a low resistance state, without the need for manual replacement‌.
PTC Behavior:
Resettable fuses utilize a Polymeric Positive Temperature Coefficient (PPTC) material. This material exhibits a significant increase in resistance as temperature rises.

Littelfuse Surface Mount Resettable Fuse China Supplier

LF 1812 Resettable Fuse PPTC 1812L SMD Self-Recovery 0.2A 0.5A 500mA 0.75A 1.1A 1.5A 2A 2.6A 3A 6V 8V 13.2V 15V 24V 30V

Overcurrent Protection Surface Mount PPTC Resettable Fuse 6V 30V 33V 60V SMD

Protección contra sobrecorriente:
When a current exceeds the fuse’s rated value flows, the PPTC material heats up, causing its resistance to increase. This increase in resistance reduces the current flow, preventing damage to the circuit.

Reinicio automático:
Once the fault is removed and the fuse cools down, the resistance decreases, allowing normal current flow to resume.

Key Features and Benefits:
Auto-reinicio:
The ability to automatically reset after a fault event makes it a reusable alternative to traditional fuses.

Protección contra sobrecorriente:
Protects circuits from damage caused by excessive current, short circuits, or overheating.

Space-Saving:
SMD packaging allows for integration into compact electronic devices.
Wide Range of Applications:
Found in various devices, including computers, teléfonos móviles, equipo medico, and automotive electronics.

Ejemplo:
Imagine a situation where a USB port on a laptop is accidentally short-circuited. A resettable fuse on the USB power line would detect the overcurrent and increase its resistance, limiting the current and preventing damage to the laptop’s power supply and other components. Once the short is removed, the fuse would reset, and the USB port would be ready to use again.