Contact electrostatic protection design of electronic engineers must be clear, ESD protector may cause abnormal product work, crash, and even damage and cause other security problems. So before the product listed, domestic or foreign testing departments are required to carry out ESD protection and other surge impact test. The contact discharge needs to achieve + 8kV, air discharge needs to achieve + 15kV, which puts forward higher requirements for the design of ESD protector.
Two main damage mechanisms of ESD protector are: heat generated by ESD current leads to thermal failure of equipment; excessive voltage induced by ESD leads to insulation breakdown. In addition to causing circuit damage, electrostatic discharge is extremely easy to cause interference to the electronic circuit. The interference of electrostatic discharge on electronic circuit in two ways. One is the conducted interference, another is radiation interference; video line protection, ESD static diode‘s main function is to suppress high voltage, prevent the insulation breakdown; electromagnetic interference of persuasion, to find a balance in the normal electromagnetic interference and products.

Analysis of video line ESD protection requirements
Electrostatic interference on video transmission depends on the size of the electrostatic voltage difference, serious damage or damage to the interface chip. High speed data line demand for ESD protection is increasing, in order not to cause high frequency distortion, USB power line and data line protection, T1/E1 protection, T3/E3 IC secondary side IC secondary side protection, HDSL SDSL, IC secondary side protection, video line protection, microcomputer protection, base station, I2C total line protection are required to ensure system capacitance as low as possible value in the selection of electrostatic and electrostatic protection design scheme of electrostatic ESD suppressor diode. Video data line has a high rate of data transmission, (the data transmission rate is as high as 480 Mbps, some video data transmission rate can reach more than 1G), thus to choose low capacitance electrostatic suppressor, usually a ESD static diode and TVS diode in series capacitor to reduce the whole line (below 3 pF), and to achieve high-speed circuit demand. According to the video line electrostatic protection demand static suppressor is simple, the following is the specific parameters of SO-08 ESD diode package tage ESD12V08S-4L electrostatic: ESD12V08S-4L parameters:
Package: SO-08
Voltage: 12V
Clamp voltage: 19V
Capacitance value: 5pF
Power: 500W

Characteristics of ESD12V08S-4L:
1, according to (tp=8/20 s) circuit, peak pulse power is 500W
2, to protect the four high-speed I/O line
3, suitable for low capacitance of the high speed interface (5pF)
4, low clamping voltage and working voltage
5, in compliance with RoHS
6, IEC61000-4-2 (ESD) + 15kV (air), 8kV (contact).
7, IEC61000-4-4 (EFT) 40A (5/50, s)
8, IEC61000-4-5 (Lightning) 24A (8/20 s)

Analysis of selection of ESD static diode ESD12V08S-4L
Electrostatic protective element product selection ultimately according to the specific needs of each customer choose the appropriate ESD model. For customers in the selection and provide product solutions, we must bear in mind that the following two principles:
The working voltage of Vdrw is more than or equal to the circuit
According to the application of the port, protection grade selection MLCV or ESD static diode, selected according to the capacitance of the transmission frequency, the higher the frequency, the device will lower the capacitance value of the capacitance value is too large, easy to cause the signal loss, therefore, must be ESD type electrostatic diode according to their own needs to choose the most suitable.