ما هو فتيل رقاقة يمكن إعادة توزيعه?

A resettable chip fuse, also known as a PTC (معامل درجة الحرارة الإيجابية) resettable fuse, is a type of surface mount device (مصلحة الارصاد الجوية) 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, السماح للتيار بالتدفق مرة أخرى.

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

SMD FUSE إعادة توزيع 1812 16رقاقة جبل السطح V 2A للحماية الزائدة

فتيل رقاقة يمكن إعادة توزيعها (PPTC) هو عنصر الحماية الزائد على أساس خصائص معامل درجة الحرارة الإيجابية للبوليمر. لديها وظيفة إعادة ضبط تلقائية وتستخدم على نطاق واسع في حماية الدائرة للمعدات الإلكترونية. فيما يلي نقاطها الأساسية:

1. الهيكل ومبدأ العمل
‌تركيبة المواد‌
It is composed of a specially treated polymer resin (such as PE polymer) والجزيئات الموصلة (أسود الكربون أو جزيئات معدنية). في ظل الظروف العادية, تشكل الجسيمات الموصلة مسارًا منخفض المقاومة (0.1-عدة أوم)‌.
‌Protection Mechanism‌
عندما يحدث التيار الزائد, يؤدي التأثير الحراري للتيار إلى ذوبان الراتنج وتمدده, 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, تبرد الجسيمات الموصلة وتتقلص, أعد الاتصال, and return to a low resistance state, without the need for manual replacement‌.
PTC Behavior:
Resettable fuses utilize a Polymeric Positive Temperature Coefficient (PPTC) مادة. 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

حماية التيار الزائد:
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.

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

Key Features and Benefits:
إعادة الضبط الذاتي:
The ability to automatically reset after a fault event makes it a reusable alternative to traditional fuses.

حماية التيار الزائد:
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, الهواتف المحمولة, المعدات الطبية, and automotive electronics.

مثال:
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.