2022-02-15
TVS transient suppression diode, as a common circuit protection component, is widely used in all walks of life. TVS diodes can be found in many fields such as automotive electronics, consumer electronics, power drives, industrial distribution, renewable energy, telecommunications, home appliances, metering instruments, medical electronics, industrial control, lighting, security systems, building control and automation, audio/video equipment, computers and their peripherals. For TVS transient suppression diode working principle and use skills, many consumer friends also confused for this, Liyang semiconductor hereby wrote this article, and you talk about the working principle of TVS transient suppression diode and use skills!
The working principle of TVS transient suppression diode
Transient voltage suppression diode, TVS diode for short, is a new type of high efficiency circuit protection device developed on the basis of voltage regulator technology. When both ends of the circuit are impacted by high energy, the TVS tube can convert the impedance values at both ends from high impedance to low impedance at a PS level response speed, instantly absorb a large current, clamp the voltage at both ends in a predetermined value, thereby protecting the precision devices in the circuit from the impact of transient high-voltage peak pulses. SO, TVS tube with PS level response speed, high surge absorption capacity, low clamp voltage, low leakage current, low capacitance, breakdown voltage deviation is small, no damage limit, small size, easy to install and other advantages, widely used in semiconductor or sensitive parts protection, diode power supply and signal circuit protection and anti-static protection.
Second, the use of TVS transient suppression diode skills
Methods/Steps
1. Determine the maximum DC or continuous operating voltage of the protected circuit, the rated standard voltage of the circuit, and the "high end" tolerance.
2. The rated reverse shutdown VWM of the transient suppression diode should be greater than or equal to the maximum operating voltage of the protected circuit. If the selected VWM is too low, the device may enter the avalanche or affect the normal operation of the circuit because the reverse leakage current is too large. Serial connection sub-voltage, parallel connection sub-current.
3. The maximum clamping voltage VC of the transient suppression diode should be less than the damage voltage of the protected circuit.
4. During the specified pulse duration, the maximum peak pulse power of the transient suppression diode PM must be greater than the peak pulse power that may occur in the protected circuit. After 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, attention must also be paid to the selection of a transient suppression diode device with a suitable capacitor C.
6. Select the polarity and packaging structure of the transient suppression diode according to its use. It is reasonable to choose bipolar transient suppression diode for AC circuit. It is more advantageous to choose transient suppression diode array for multi-line protection.
Temperature consideration. Transient voltage suppressors can operate between -55 and +150 ° C. If the transient suppression diode is required to operate at a changing temperature, its reverse leakage current ID is increased with increasing; The power consumption decreases with the increase of the junction temperature of the transient suppression diode, from +25℃ to +175℃, and the linear decrease of about 50% rain breakdown voltage VBR increases with the increase of temperature by a certain coefficient. Therefore, it is necessary to consult the relevant product information and consider the impact of temperature changes on its characteristics.
