What is TVS?

◦ Rapid response in the event of an overvoltage event, dissipating excess voltage to ground

◦ Maintains high impedance state during normal operation (does not affect the circuit)

◦Reusable protection element

◦Semtech has over 30 years of experience and produces over 10 billion units per year.

Operating principle

◦Maintains high impedance state under normal conditions

◦When a transient voltage occurs, it transitions to a low impedance state and releases the overvoltage to ground.

The overvoltage threat

◦ Electrostatic discharge (ESD): occurs when contact occurs with the human body or objects

◦ Electrical Fast Transient (EFT): occurs during switching operations

Surge: A high-energy pulse generated by lightning or power grid switching.

◦ Other transient overvoltage events

Recent issues with electronic devices

High density mounting on boards

◦Increased number of external connectors

◦Decreased surge resistance due to miniaturization of LSIs

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High-speed and highly integrated electronic devices are vulnerable to transient voltages

The Importance of Circuit Protection

◦ESD penetration can lead to equipment failure and destruction

◦The cause of ESD damage is often not immediately identifiable.

◦ Essential for improving equipment reliability and extending its lifespan

◦ Essential protection measures to comply with international standards

Excellent electrical properties
・Low clamp voltage
・Low capacitance
-Low leakage current
- High-speed response (sub-nanosecond level)

Excellent protection
・Almost no degradation due to ESD
・Low residual energy after surge application
- Faster response than other protection elements (Polymer, MLV, Zenor)
-High ESD resistance: Compliant with IEC 61000-4-X

Flexibility in design and implementation
・Small leadless package with small mounting area
・Supports a wide range of applications including consumer, industrial and automotive
- Product lineup optimized for various interfaces
・AEC-Q100 certified products are also available (for automotive applications)

Select a product that is appropriate for the operating voltage of the circuit to be protected. If the operating voltage is too low, the circuit will be conductive during normal operation, and if it is too high, the protective performance may be insufficient. In general, the operating voltage of a protection element is set to a value slightly higher than the operating voltage of the circuit.

Select according to the number of signal lines that need to be protected. The number of channels required varies depending on the interface, such as 4 lines for USB and 19 lines for HDMI. By selecting an array product with multiple channels as necessary, the mounting area can be reduced.

In interfaces that perform high-speed data transfer, capacitance affects signal quality. For high-speed interfaces such as USB 3.x, HDMI, and DisplayPort, products with low capacitance (1pF or less) are recommended.

When mounting space is limited, choose a small package product. The μClamp series is particularly small and suitable for space-limited devices such as smartphones and wearable devices.

Select according to the ESD protection level required. In recent years, even ±8kV of IEC 61000-4-2 Level 4 may not be enough. For particularly harsh environments, consider products with ±15kV or more.

For automotive applications, select AEC-Q100 certified products. Also, by selecting products that comply with various interface standards (USB-IF, HDMI, DisplayPort, etc.), you can ensure the protection performance required for standard compliance.