The S20K420E2K1 is a varistor manufactured by EPCOS (TDK), designed to protect electronic circuits from transient overvoltages. It provides a reliable solution for diverting excess voltage caused by events such as lightning strikes, inductive load switching, and electrostatic discharge (ESD), ensuring the safe operation and longevity of sensitive electronic components and equipment.

Applications

• Power supplies (AC/DC and DC/DC converters)
• Industrial control systems
• Surge protection devices (SPDs)
• Consumer electronics (TVs, appliances)
• Telecommunications equipment

Features

• High surge current handling capability
• Fast response time to transient overvoltages
• Compliance with UL, CSA, VDE, and IEC safety standards
• Wide operating voltage range
• RoHS compliant (Restriction of Hazardous Substances)
• Lead-free terminals for enhanced environmental compliance

Benefits

• Effective protection against transient voltage surges
• Improved reliability and extended lifespan of electronic devices
• Reduced downtime and maintenance costs
• Compliance with industry safety and environmental regulations
• Easy integration into existing circuit designs
• Cost-effective solution for transient voltage suppression

Additional Details

The S20K420E2K1 varistor has a varistor voltage of 420V, meaning that it will start conducting significantly and clamp the voltage when the voltage across it exceeds 420V. The 'S20' indicates a disk size of 20mm, contributing to a higher surge current handling capacity. The 'E2K1' suffix specifies the lead configuration and packaging. Design engineers should consult the EPCOS (TDK) datasheet for detailed specifications, including the maximum surge current rating (typically specified for an 8/20 µs pulse), clamping voltage characteristics, energy absorption capabilities, and the operating temperature range. Selection of the appropriate varistor based on these parameters is crucial for optimal circuit protection. This device is designed for through-hole mounting. The ambient operating temperature should be carefully considered, as it can affect the varistor's performance and lifespan. It is essential to adhere to the derating curves provided in the datasheet for safe operation at elevated temperatures. The varistor effectively acts as a voltage-dependent resistor, rapidly reducing its resistance when the voltage exceeds its rated threshold, thus diverting surge current and protecting sensitive downstream components.