SMS3.3.TCT Circuit Protection

SMS3.3.TCT Application Field and Working Principle

Surface-Mounted Silicon TVS Diode (SMS3.3.TCT) is a three-terminal surface-mount silicon device designed to protect low voltage, high frequency electronic circuits against voltage transients induced by a variety of sources, including inductive switching packages and lightning. It is especially suited for AC circuit protection applications requiring low leakage current and high breakdown voltage.

The SMS3.3.TCT is an unidirectional device designed to protect on-board components from the effects of lightning and other transient voltage surges, surges in the supply lines, and electrostatic discharge (ESD). It can also be used for overvoltage protection or crowbar circuit protection.

The SMS3.3.TCT\'s working principle is based on the principle that a voltage across a diode will be attenuated according to the approximate equation Vout = Vin * (1 – Ф). Ф is the rectification coefficient, which is the ratio of the forward bias to the total bias. This phenomenon is very useful in overvoltage protection because the rectifying diode in the SMS3.3.TCT will cause attenuating the high transient voltages which attempt to flow in an unwanted direction.

The SMS3.3.TCT is particularly suitable for AC circuits protection with high AC reflection coefficient, as it has a low capacitance. This low capacitance provides a fast switching speed, making the device suitable for transient protection in AC applications. The SMS3.3.TCT can also be used for attenuating high frequencies, such as in power supplies, electric garage doors, and motor speed control systems. With its high surge capability, it can also be used to protect sensitive electronics in consumer appliances from voltage transients caused by radio frequency interference (RFI).

To protect AC circuits, SMS3.3.TCT also features a low dynamic resistance, making it suitable for low power supply applications. Furthermore, SMS3.3.TCT has an extra breakdown voltage of up to 12kV for higher circuit protection requirements. This indicates that it can easily prevent transmitted noise and voltage transients at the power input.

Finally, SMS3.3.TCT features a capacitor between its anode and cathode for improved ESD protection. This capacitor will temporarily store the energy of the ESD and thus dissipate it before it can reach the vulnerable circuits. This helps to protect the connected ICs and other electronic circuits from damage caused by electrostatic discharge