How do you test a TVS diode?
The Diode Test procedure is conducted as follows:
- Make certain a) all power to the circuit is OFF and b) no voltage exists at the diode. Voltage may be present in the circuit due to charged capacitors.
- Turn the dial (rotary switch) to Diode Test mode.
- Connect the test leads to the diode.
- Reverse the test leads.
Why is TVS diode used in a circuit?
TVS Diodes are used to protect semiconductor components from high-voltage transients. Their p-n junctions have a larger cross-sectional area than those of a normal diode, allowing them to conduct large currents to ground without sustaining damage.
What is a TVS diode used for?
TVS diodes are used in ICs (integrated circuits) to protect against overvoltage and the effects of arcs, EFT (Electrical Fast Transients), ESD (Electrostatic Discharge), inductive load switching, and even lightning strikes.
Can you test a diode in circuit?
Often, a failed diode will allow current to pass in either direction unimpeded. You can test a diode using a multimeter. There are many different styles and brands of multimeter, but they all function essentially the same way and offer similar features.
How do TVS diodes fail?
By nature, a TVS device will fail when subjected to a transient beyond its designed capability. If the circuit or system is not properly fused, a shorted TVS device can become a safety hazard conducting operating currents through the return path.
What is TVS diode working voltage?
Commonly, 4/20 mA input terminals have a nominal voltage of 24 V, with a maximum DC voltage tolerance of 33 V. Any TVS diode selected must have a VRWM of 33 V or greater to enable this operation. There are many options for TVS diodes that meet this requirement.
What is the difference between Zener and TVS diode?
2-6(b), a Zener diode clamps input voltage to a constant voltage and supplies clamped voltage to other semiconductor devices. Thus, a TVS diode absorbs surge voltage to protect other semiconductor devices, whereas a Zener diode provides constant voltage to other semiconductor devices.
What is breakdown voltage of TVS diode?
The breakdown voltage (VBR) is the voltage where a TVS diode begins to conduct current, defined typically at 1 mA leakage. VBR defines the inflection point on the diode curve where the leakage beings to increase exponentially, which is typically referred as the diode ‘turning on’.
Is a TVS diode a zener diode?
One common misconception is that TVS diodes and Zener diodes are the same thing, and I often hear TVS diodes referred to as “Zeners”. TVS diodes and Zener diodes are engineered for very different applications. Zener diodes are designed to regulate voltage and therefore operate in the breakdown region (Figure 2).