Product Description
The MZ126A is a typical PTC thermistor for overcurrent protection, often called a resettable fuse or polymer positive temperature coefficient thermistor (PPTC). Its core function is to provide automatically resettable overcurrent and overtemperature protection for electronic circuits. When a short circuit or overload causes abnormally high current, the MZ126A quickly switches from a low-resistance state to a high-resistance state, effectively limiting the current and protecting subsequent expensive electronic components. Once the fault is resolved and power is disconnected, the device cools and automatically returns to its low-resistance state, restoring normal circuit operation without the need for manual replacement.
Specification
Product Name: MZ126A PTC Thermistor
R25 : 12Ω±30%
Max Diameter : 10mm
Withstand Current Capability : 2A
Withstand Voltage : 270V
Application : Electronics
Color : Green
Features
Self-resetting: Unlike traditional fuses that blow once, the MZ126A automatically resets after the fault is cleared, significantly reducing maintenance costs and downtime, while improving equipment reliability.
Dual Overcurrent and Overtemperature Protection: Its triggering is based on self-heating. Whether it's excessive current (I²R heating) or excessive ambient temperature, it responds as soon as the temperature exceeds its trip point, providing dual protection.
Fast Response: It reacts quickly to abnormal overcurrent, transitioning from a low-resistance state to a high-resistance state within milliseconds, effectively suppressing high current surges and preventing fault escalation.
High Reliability: Its solid-state polymer construction, with no moving parts, is shock and vibration resistant and can provide over thousands of protection cycles.
Compact Size: It typically uses radial leads for a compact, space-saving design.
Application
The MZ126A PTC thermistor is widely used in various electronic devices due to its excellent protection performance and convenience:
Power Port Protection:
Power Adapters/Chargers: Provides input/output overcurrent protection in primary and secondary circuits.
USB Ports: Protects USB interfaces from damage due to short circuits or hot-plug surges.
Battery Overcurrent Protection:
Lithium Battery Packs: Widely used in battery packs for mobile phones, laptops, tablets, Bluetooth headsets, power tools, and other products, preventing overheating and combustion risks caused by overcharging and short circuits.
Motor Protection:
Small Motors: When motors in air conditioners, washing machines, and fans stall or are overloaded, causing a surge in current, the MZ126A activates to protect the motor coils from burnout.
Automotive Electronics:
Applied to ECUs (Electronic Control Units), LED headlights, entertainment systems, and other automotive electronic modules, providing robust protection.
Consumer Electronics and Home Appliances:
Speakers: Protect audio amplifiers and tweeters.
Motherboards: Protect the power supply circuits of core components such as the CPU and memory.
Various PCB boards inside TVs, monitors, smart home devices, etc.
