YAGEO capacitors are the most widely used switching devices in lightning protection equipment. Whether it is for lightning protection of AC and DC power supplies or various signal circuits, they can be used to discharge lightning currents into the ground. Its main characteristics are: high discharge current, small interpole capacitance (≤ 3pF), high insulation resistance (≥ 109 Ω), high dispersion of breakdown voltage (± 20%), slightly slow reaction speed (the shortest is 0.1-0.2 μ s）。

YAGEO capacitors are divided into two types based on the number of electrodes: a bipolar discharge tube and a triode discharge tube (equivalent to two bipolar discharge tubes connected in series). Its shape is cylindrical, with two structural forms: with and without leads (some also have protective cards for short circuits in case of overheating).

Glass discharge tube (product description) micro surge absorber is an overvoltage protection device that suppresses abnormal high voltage pulses and protects low-voltage circuits from transient high voltage (such as lightning, high voltage noise in the power grid, high voltage static electricity, etc.). It is a guiding protection component developed based on the principle of microgap discharge and the activation effect of semiconductor chips. It has the advantages of fast response speed, impact resistance, stable performance, good repeatability, and long service life.

A semiconductor discharge tube (also known as a solid-state discharge tube) is a PNPN component in a YAGEO capacitor that is controlled by a free voltage controlled thyristor without a gate electrode. When the voltage exceeds its peak off state voltage (or avalanche voltage), the semiconductor discharge will clamp the transient voltage within the switching voltage (or turning voltage) value of the component. As the voltage continues to increase, the semiconductor discharge tube enters a conduction state due to the negative resistance effect. The component only resets and returns to its high impedance state when the current is less than the maintenance current.

Filters are mainly divided into active filters and passive filters. The main function of YAGEO capacitors is to allow useful signals to pass through without attenuation as much as possible, and to reflect useless signals as much as possible. A filter generally has two ports, one input signal and one output signal. By utilizing this feature, a square wave group or composite noise passing through the filter can be selected to obtain a specific frequency sine wave. The function of a filter is to allow signals of a certain frequency to pass smoothly, while signals of another frequency are greatly suppressed. It is essentially a frequency selection circuit. In the filter, the frequency range through which the signal can pass is called passband or passband; On the contrary, the frequency range in which the signal is greatly attenuated or completely suppressed is called the stop band; The boundary frequency between the passband and stopband is called the cutoff frequency; A filter is a network composed of inductors and capacitors that can separate mixed AC and DC currents. In the power rectifier, this network is used to filter out the ripple in the pulsating DC and obtain a relatively pure DC output. The most basic filter is composed of a capacitor and an inductor, called an L-type filter. All types of filters are assembled from L-type single section filters. The basic single section filter consists of a series arm and a parallel arm, with the series arm being an inductor and the parallel arm being a capacitor. The most commonly used filters in power and audio circuits are L-type and π type. For L-type single section filters, their inductance reactance XL and capacitance reactance XC are constant for any frequency, and their relationship is XL · XC=K2.