As an engineer, the early may be encountered in contact with the product do not know how to use, for example: transient suppression diode, we all know, just in the face of these will find a simple and fast method. Then the transient suppression diode, the following is tage electronic technology small to give you a few suggestions:
The use of transient suppression diodes
1. Determine the maximum DC or continuous operating voltage of the protected circuit, the rated voltage of the circuit and the tolerance of the "high end".
2, transient suppression diode rated reverse turn off VWM should be greater than or equal to the maximum operating voltage of the protected circuit. If the selection of VWM is too low, the device may enter the avalanche or the reverse leakage current is too large to affect the normal operation of the circuit. Serial connected sub voltage, parallel connection current.
3, transient suppression diode clamp voltage should be less than the maximum VC protected damage voltage circuit.
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Transient suppression diode)
4, in the prescribed pulse duration, transient suppression diode maximum peak pulse power consumption of PM must be greater than the protection circuit may occur within the peak pulse power. In determining the maximum clamping voltage, the peak pulse current should be greater than the transient surge current.
5, for the protection of the data interface circuit, we must also pay attention to the selection of a suitable capacitor C transient suppression diode device.
6, based on the use of transient suppression diode polarity and encapsulation structure. Bipolar transient suppression diode is more reasonable for AC circuit, and multi line protection is more favorable for transient suppression diode array.
7, temperature considerations. Transient voltage suppressor can work in 55~+150 c.. If you need transient suppression diode in a changing temperature, due to the reverse leakage current of ID is increased with the increase of power consumption; with the increase of transient suppression diode junction temperature decreases from +25 DEG to +175 DEG, approximately linear decrease 50% rain breakdown voltage VBR with the increase of temperature increase by a certain coefficient. Therefore, it is necessary to consult the relevant product information, consider the impact of temperature changes on its characteristics.
The selection principle of transient suppression diode
(1), VC (MAX) voltage clamp voltage is not greater than the maximum allowable safety circuit.
(2), the maximum reverse working voltage (VRWM voltage) is not less than the maximum operating voltage of the circuit, the general can choose VRWM is equal to or slightly higher than the maximum operating voltage of the circuit.
(3), the maximum rated pulse power, must be greater than the circuit in the maximum transient surge power.
From the electronic related article:
Main characteristic parameters and selection of TVS transient diode
TVS transient diode function and application range