4.0SMDJ20A

Transient voltage suppressor diodes (TVSs) are a form of semiconductor device that is capable of absorbing and responding to high electrical voltages and currents until their destruction. They are used in a variety of applications, from power supplies to motor vehicle electronics, to protect circuits and equipment from potentially damaging transient spikes of voltage. The 4.0SMDJ20A is a type of unidirectional TVS diode specifically designed for protection against high-energy ESD strikes and lightning surges.

Characteristics

The 4.0SMDJ20A is a glass-passivated, bidirectional breakover diode constructed using an anode and a cathode. It offers an unidirectional clamping action that minimizes continuous reverse leakage current and generates a low peak pulse current. This diode is rated for a peak standoff voltage of 5kV and a reverse standoff voltage of 4kV. It has a low capacitance of 8pF (typ) and a maximum peak current of 8A.

Applications

Due to its superior electrical characteristics, the 4.0SMDJ20A TVS diode is commonly used in high-performance applications to protect sensitive electronic equipment from high energy ESD events and lightning surges. It can be used with transceiver designs, Ethernet ports, and digital signal ICs to negate the possibility of damage from minor static discharges and reduce the risk of data loss. The 4.0SMDJ20A diode is also very effective for protecting communication and power lines from overvoltage events.

Working Principle

The working principle of the 4.0SMDJ20A TVS diode is based on the idea of a Zener breakdown. When the voltage level on the anode side of the diode is greater than the voltage on the cathode side, it will separate to create an electron-hole pair. This will lower the voltage on the anode side by means of dissipating the excess energy as heat within the junction, thereby protecting the device from damage. If the voltage level on either side exceeds the maximum peak breakdown voltage, the diode will break down, creating a high-current path.