Problems that should be paid attention to in the application of TVS pipe
The relation between the absorbed power (peak value) of transient voltage and the pulse width of transient voltage. For the maintenance of small current load, we can consciously add current limiting resistance in the line. As long as the resistance value of current limiting resistance is appropriate, it will not affect the normal operation of the line, but the current generated by the current limiting resistance on the disturbance will be greatly reduced. Therefore, it is possible to select TVS tubes with smaller peak power to maintain low current load lines.
To suppress the repeated transient voltage, it is particularly worth noting whether the steady state average power of TVS tube is within the safe scale.
As a semiconductor device, TVS tube should pay attention to the problem of derating when the ambient temperature rises. Pay special attention to the lead length of TVS tube and its relative spacing with the line to be maintained. When there is no TVS tube with appropriate voltage for use, it is allowed to use multiple TVS tubes in series. The maximum current of the series tube depends on the one with the least current absorption capacity. The peak absorption power is equal to the product of the sum of this current and the series tube voltage.
The junction capacitance of a TVS tube is a key factor affecting its application in high-speed lines. In this case, a TVS tube is generally connected with a fast recovery diode back to back. Because the fast recovery diode has a small junction capacitance, the equivalent capacitance of the two in series is also small, which can meet the requirements of high-frequency application.
Various electronic systems and communication networks are often subject to external electromagnetic disturbances, which mainly come from the transient process of power lines, lightning strikes, and world radio. These disturbances will lead to system action errors and even hardware damage. For these problems, comprehensive preventive and maintenance measures should be taken. It is a good plan to plan and select appropriate silicon transient absorption diodes to deal with transient disturbances. However, as the electronic industry explores more electronic products that improve efficiency, add functions and improve integration, planning and providing a complete circuit maintenance plan will constitute another innovation in circuit maintenance skills.
