Low Capacitance Gas Discharge Tubes - SX5 Series RoHS & HF Compliant

SX5 0 - 230X SMDT.pdf

Structure

Some gas discharge tubes use glass as the encapsulation shell of the tube. Some also use ceramics as the package shell, and the discharge tube is filled with an inert gas with stable electrical properties (such as argon and neon gas, etc.). The discharge electrodes of the commonly used discharge tube are generally two or three, and the electrodes are separated by an inert gas. . According to the setting of the number of electrodes, the discharge tube can be divided into two-pole and three-pole discharge tubes.
The ceramic diode discharge tube is composed of pure iron electrode, nickel-chromium-cobalt alloy cap, silver-copper welding cap and ceramic tube body and other main components. The discharge electrodes in the tube are coated with radioactive oxides, and the inner wall of the tube is also coated with radioactive elements to improve the discharge characteristics. The discharge electrode mainly has two structures: rod-shaped and cup-shaped. In the discharge tube of the rod-shaped electrode, a cylindrical heat shield is installed between the electrode and the wall of the tube body. The heat screen can make the ceramic tube body heat tend to Uniform, so that there will be no local overheating and cause the tube to break. The inside of the heat shield is also coated with radioactive oxides to further reduce discharge dispersion. In the discharge tube of the cup-shaped electrode, molybdenum mesh is installed at the mouth of the cup, and cesium element is installed in the cup, which also reduces the dispersion of discharge.
The three-electrode discharge tube is also composed of pure iron electrodes, nickel-chromium-cobalt alloy caps, silver-copper welding caps, and ceramic tubes. Different from the diode discharge tube, a nickel-chromium-cobalt alloy cylinder is added to the three-electrode discharge tube as the third pole, that is, the ground electrode.

Principle

The working principle of the discharge tube is gas gap discharge. When a certain voltage is applied between the two poles of the discharge tube, an uneven electric field is generated between the electrodes: under the action of this electric field, the gas in the tube begins to dissociate. When the applied voltage increases to make the gap between the electrodes When the field strength exceeds the dielectric strength of the gas, the gap between the two poles will be broken down by the discharge, and the original insulating state will be transformed into a conductive state. After the conduction, the voltage between the two poles of the discharge tube will remain at the residual voltage level determined by the discharge arc. , this residual voltage is generally very low, so that the electronic equipment connected in parallel with the discharge tube is protected from overvoltage damage

Features

1. RoHS & HF compliant
2. SMD Structure
3. DC Spark-over voltage: 70~5000V 4. Low Capacitance
5. Agency Recognition : UL
6. Operating temperature:-30°C ~ +85°C Storage
temperature:-40°C ~ +115°C

Warehouse Storage Conditions of Products

· Storage Conditions:
1. Storage Temperature: -10°C~+40°C
2. Relative Humidity:≤75%RH
3. Keep away from corrosive atmosphere and sunlight. · Period of Storage: 1 year

Recommended Applications

1. Cable Modem
2. xDSL
3. Set-Top Box
4. TV sets
5. Power supplier
6. Consumer electronics