Technical specifications and model selection guidelines for TVs tubes and ESD tubes - recommended by jialichuang

TVS Tube and ESD Technical indicators and model selection guide of pipe

Transient voltage suppressor is abbreviated as TVS, It is a high efficiency protection device in the form of diodes . When TVS When the two poles of the diode are impacted by the reverse transient high energy , It changes the high impedance between its poles into low impedance , Absorb surge power up to several kilowatts , Clamp the voltage between the two poles to a predetermined value , Effectively protect precision components in electronic circuits , Protect from all kinds of surge pulse damage . Because it has fast response time 、 High transient power 、 Low leakage current 、 Small deviation of breakdown voltage 、 The clamping voltage is easy to control 、 No damage limit 、 Small size and other advantages .

ESD Electrostatic protective tube is a common overvoltage 、 Electrostatic protection elements , Protect sensitive circuits in electronic equipment from static electricity .ESD The electrostatic protection tube is connected in parallel in the circuit , When the circuit operates normally ,ESD The electrostatic protection tube is in a high resistance state , It will not affect the normal operation of the line ; When the circuit has abnormal overvoltage and breakdown voltage , Quickly change from high resistance state to low resistance state , Give instantaneous current to provide impedance conduction path , Clamp the abnormal voltage at a safe level , So as to protect the protected IC Or line .

Technical indicators

Ipp: Maximum reverse peak current , The bigger this is , Better product performance .
[email protected]： Clamp voltage , Reach the maximum current Ipp Clamping voltage value at .
Vrwm： Maximum directional operating voltage , Protected signals , Its normal working voltage should not exceed this voltage .
Vbr： Reverse breakdown voltage , When the reverse voltage exceeds this value , The reverse current will increase sharply .
Cj： Junction capacitance , It's usually pF Level , Used on high-speed signal lines , such as USB2.0 Of D+ and D-.
Ppp： The largest one tested Ipp Multiply by the clamping voltage at this point Vc.

Selection Guide

Vrwm It shall not be less than the working voltage of the protected signal . From the point of view of reducing leakage ,Vrwm The higher the working voltage than the protection signal , The smaller the leakage current . In terms of protection strength ,Vrwm The closer to the signal operating voltage , Clamp voltage of the tube Vc The lower the , The better the protection of the signal .

ESD Tube and TVS The protection grade of the pipe should be greater than the protection grade required by the product itself .ESD Tube and TVS Electrostatic clamping voltage of the tube 、 The lower the surge clamp voltage, the better . The protection performance of the pipe is mainly related to the clamping voltage .

TVS Power requirements of tubes ： Suppose you want to pass 200V Surge of , The clamping voltage required is 20V within , The internal resistance of surge tester is 2Ω, So the maximum output current is （200V-20V）/2Ω=90A, The tube power should be selected at 90A*20V=1800W Power above . If this TVS The clamping voltage of the tube is less than 20V, The power requirements will be lower .

Save the flow ： First look at Vrwm Reverse operating voltage , Look again Vc Clamp voltage , And then look Ppp Peak pulse power .

Product recommendation

Reference to the original ：《TVS Tube and ESD Technical indicators and model selection guide of pipe 》