SMAJ18

Due to market price fluctuations, if you need to purchase or consult the price. You can contact us or emial to us:   sales@allicdata.com

Transient Voltage Suppressor (TVS) diodes are used to protect sensitive electronic components and circuits from overvoltage or electro-static discharge (ESD). As the applications of electronics have become increasingly complex, so have the demands on circuit protection. This has driven the development of specialized protection components, such as the SMAJ18 TVS diode. This article explores the application field of the SMAJ18 and explains its working principle.

TVS Diode Basics

TVS diodes, also known as surge-suppression protection diodes, are designed to protect components from overvoltage or destructive transients. They are capable of safely dissipating large, destructive surges of energy caused by lightning, electrostatic discharge, and other sources. In comparison, the transient suppression capability of standard diode-based protection circuits is limited.

A TVS diode typically consists of a pair of diodes connected in inverse parallel direction with a junction capacitor between them. As the voltage across the TVS diode increases, the forward voltage of the diodes decreases and the junction capacitor begins to conduct. This protects against the surge of high energy, and the TVS diode begins to conduct and safely dissipate the energy.

SMAJ18 Application Field

The SMAJ18 TVS diode was designed to provide superior over voltage and ESD protection for digital and delicate analog components housed in ultra-low power applications. This 18V device is designed for bi-directional AC surge and ESD protection, and is ideal for protecting sensors and other low-voltage components. It is also suitable for protecting applications where the power supply voltage can be up to 30V.

The SMAJ18 is designed for applications in automotive, industrial and consumer electronics. The device offers an extremely low forward voltage drop of less than 0.2V at 1mA current, making it well suited for ultra-low power applications and data systems. Additionally, the device features an IEC 61000-4-2 ESD rating of 4KV contact and 8KV air discharge.

SMAJ18 Working Principle

The SMAJ18 is a TVS diode consisting of two back-to-back Zener diodes with a junction capacitor between them. During over-voltage or ESD, the junction capacitor begins to conduct and provides protection against high-energy surges. The device features a low forward voltage drop, and an integrated MOV architecture for enhanced ESD tolerance.

The device is designed to dissipate energy steadily to ensure that a surge is not passed on to sensitive circuits and components. During an over-voltage event, the SMAJ18 will quickly conduct the current to ground, effectively preventing it from passing to sensitive circuits. The device also reduces leakage current and ensures that the circuit is protected from over-current and over-temperature events.

The SMAJ18 is designed to provide superior protection for ultra-low power electronics applications in automotive, industrial and consumer sectors. The device offers excellent performance for over-voltage and ESD protection, and can be used in bi-directional AC surge and ESD protection applications. The device can handle a wide input voltage range from 5 to 30V, and is designed to dissipate energy safely and quickly.

The specific data is subject to PDF, and the above content is for reference