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title: Creating a Class H xDSL Line Driver Protection Solution with the Biased SIDACtor® Protection Thyristor Application Note
---

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# Download!  Creating a Class H xDSL Line Driver Protection Solution with the Biased SIDACtor® Protection Thyristor Application Note

![Class H xDSL Line Driver Protection](https://info.littelfuse.com/hs-fs/hubfs/Electronics/Landing_Page_Images/SIDACtor_ClassH_xDSL_LineDriver_App_Note_image.jpg?width=170&name=SIDACtor_ClassH_xDSL_LineDriver_App_Note_image.jpg "Class H xDSL Line Driver Protection")

Today, most telephone lines are located in outdoor environments. This vulnerability can expose the xDSL chipsets or integrated circuits to induced surges from lightning and other electrical transients. Therefore, the circuit protection devices that safeguard them must be very robust and yet have very low capacitance to maintain signal integrity.

As the global leader in circuit protection, Littelfuse designed the Biased SIDACtor Tertiary Protection Thyristor (SDP0240T023G6) as the perfectly balanced broadband protection solution. This device offers both extremely low capacitance and high surge tolerance to protect modern xDSL chipsets from damage or premature failure. The SDP0240T023G6 provides a faster response to surges for improved ESD, lightning and power fault surge protection.

Want to learn more about this robust, solid-state component? Download your free application note today to explore: 

Download your free copy to learn about:

- The key benefits of silicon crowbar technology, including lower overshoot voltages and improved power fault surge protection
- The device’s outstanding surge capability delivered  
  in a compact, surface-mount package
- The component’s compatibility with DSL bandplans  
  up to and including 30 MHz
- How the component’s off-state voltage and leakage  
  current make it ideal for Class H DSL line drivers
- A non-biased capacitance variance vs. line  
  voltage chart
- A diagram showing an optimized overvoltage  
  protection configuration for xDSL line drivers

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