How much do you know about electrostatic protection components? ESD (electrostatic discharge protection devices), also known as transient voltage suppression diode array (TVS Array), is a multi-channel or single-channel ESD protection device with specific functions designed by multiple TVs grains or diodes in different layouts. It is mainly used for electrostatic protection of various communication interfaces, Circuit design engineers can select ESD electrostatic protection diodes in different packaging forms according to circuit board layout and interface type.
1、 ESD electrostatic protection component selection guide
1) The cut-off voltage of ESD electrostatic diode shall be greater than the maximum working voltage in the circuit;
2) For the selection of pulse peak current IPP and maximum clamping voltage VC, the appropriate IPP model shall be selected according to the maximum surge current that may appear on the line. It should be noted that the VC at this time shall be less than the maximum peak voltage that the protected chip can withstand;
3) When used for signal transmission circuit protection, pay attention to the frequency or transmission rate of the transmitted signal. When the signal frequency or transmission rate is high, ESD electrostatic diodes with low capacitance series shall be selected;
4) Select the appropriate package according to the circuit design layout and the number of protected lines. The size of ESD package can reflect the protection level of devices to a certain extent. Generally, the larger the package, the larger the ESD chip area that can be accommodated, and the higher the protection level, and vice versa.
2、 Precautions for selection of ESD electrostatic protection components
1) ESD is generally used for electrostatic protection of various communication ports. In some high-speed data lines, such as USB3.0, HDMI, IEEE1394 and other interfaces, the junction capacitance of ESD electrostatic protection diode should be as small as possible to avoid affecting the communication quality;
2) ESD can be divided into unidirectional (a) and bidirectional (c). It can be selected according to the working signal. Unidirectional ESD or bidirectional ESD can be selected for unipolar signals, and bidirectional ESD should be selected for bipolar signals;
3) The specific type of ESD electrostatic diode to be selected for electrostatic protection also needs to be selected under the guidance of professional electronic engineers;
3、 Application of ESD electrostatic protection components
ESD electrostatic protection components are widely used in communication lines and I / O ports of electronic products such as communication, security, industry, automobile, consumer products and intelligent wearable devices.