The Transient Threat: Why USB-PD Needs Surge Protection

USB Type-C with Power Delivery (USB PD) is rapidly becoming the universal standard for fast charging and high-speed data transfer across smartphones, laptops, tablets, and industrial devices. As support for up to 240 watts of power increases, so does the risk of electrical overstress (EOS), electrostatic discharge (ESD), and transient voltage surges—all of which can severely damage sensitive circuitry.

This in-depth technical whitepaper from Semtech explains how SurgeSwitch® protection technology offers a more effective and reliable solution than conventional TVS diodes. Engineers will gain essential knowledge for protecting modern USB-C designs in high-voltage environments.

What You Will Learn in This Whitepaper:

• The key weaknesses of traditional TVS diodes in high-wattage USB-C applications

• How SurgeSwitch® uses advanced MOSFET-based architecture for superior clamping and surge response

• Real-world test results that show performance under repeated ESD and surge events

• Guidance on selecting the right SurgeSwitch® product based on USB PD voltage levels

• Application-specific integration strategies for consumer electronics and industrial USB-C systems

Why Engineers Should Download This Whitepaper

If you are developing or maintaining USB-C Power Delivery systems, you need protection solutions that match the pace of increasing voltage, current, and design complexity. This whitepaper delivers evidence-based insights on how SurgeSwitch® protects your devices from damage, downtime, and customer dissatisfaction.

Optimize your designs for reliability, safety, and performance.

Download the whitepaper to stay ahead in high-speed USB-C innovation.

 

Whitepaper Introduction

The Universal Serial Bus (USB) is a ubiquitous connectivity solution that has become an integral part of our daily lives. USB has become very popular because of its ease of use, fast data transfer rate, and quick charging capabilities. Today, many popular electronic devices, such as smartphones, smartwatches, headphones, gaming consoles, WiFi adapters, tablets, and laptops, feature at least one USB port. Previously, each device required a dedicated charger, resulting in the need to carry multiple chargers during travel. 

However, introducing USB Type-C Power Delivery (USB-PD) has revolutionized charging capabilities. USB Type-C with Power Delivery allows for increased power transmission, enabling a single charger cable to charge multiple devices through their USB ports. While USB-PD enables the convenience of using a single cable to charge multiple devices, the increased power transmission capability also introduces higher risks. 

With the latest USB-PD specification supporting up to 240W of power delivery over compliant USB cables, the potential for transient overvoltages and surges has increased correspondingly. As devices are frequently plugged in and unplugged from USB Type-C ports, these ports face routine exposure to Electrical Overstress (EOS) and Electrostatic Discharge (ESD) events. Given the higher power levels involved, it is crucial to provide robust safeguards for USB Type-C ports of the devices and the inside ICs to protect from the dangers posed by the ESD and surge threats. 

This white paper aims to detail protection solutions designed to mitigate risks and safeguard the VBus line (power line) in USB-PD implementations, ensuring the safe and reliable operation of USB Type-C ports and connected devices despite the increased power delivery capabilities. 

What is USB-PD?

USB-PD is an advanced fast-charging technology built upon the USB Type-C standard. It operates based on a charging specification to maximize the power delivered to a connected device. The USB-PD specification defines how devices can utilize the USB Type-C connector for supplying power, as well as how these devices are identified and managed during the power delivery process. A key feature of USB-PD is that it enables devices to communicate and negotiate with each other over a dedicated communications channel on the USB Type-C connector before actually transmitting or receiving power. This allows devices to obtain or provide only the required power, preventing overcharging or undercharging issues.