Vishay Introduces Resettable Polymer PTC Thermistor Series for Low-Voltage Circuit Protection

Vishay Intertechnology has introduced six new surface-mount polymer PTC thermistor series for low-voltage overcurrent protection. The devices provide resettable protection for electronic circuits and are available in package sizes from 0603 through to 2920.

The new range covers holding currents from 20mA to 5A and trip currents up to 10A. Resistance is specified as low as 5mΩ on selected devices, while trip times are as short as 50ms.

Six Series Across a Wide Current Range

Rather than introducing a single device, Vishay has released six series covering different package sizes and current ratings. The range includes the PPTC0603E3, PPTC0805E3, PPTC1206E3, PPTC1210E3, PPTC1812E3, and PPTC2920E3.

According to Vishay, the series allows engineers to select resettable overcurrent protection based on both PCB area and current requirements, from compact portable electronics through to higher-current industrial equipment.

The lower resistance of the new devices is intended to reduce voltage drop during normal operation while maintaining overcurrent protection when a fault occurs.

Resettable Overcurrent Protection

Polymer PTC thermistors differ from conventional fuses in that they return to a low-resistance state after the fault has been removed and the device has cooled. This removes the need to replace the protection device following every overcurrent event.

Vishay lists applications including USB Type-C ports, Power over Ethernet equipment, battery-powered electronics, industrial automation systems, and home automation products.

Manufacturing Support

All six series are supplied in surface-mount packages suitable for lead-free reflow soldering at temperatures up to 260°C.

The devices are RoHS compliant and halogen-free. Vishay also provides SPICE models together with 3D CAD files to support circuit simulation and PCB layout.

Samples and production quantities are available now.

Learn more and read the original announcement at Vishay's website.

Technology Overview

The Vishay PPTC0603E3, PPTC0805E3, PPTC1206E3, PPTC1210E3, PPTC1812E3, and PPTC2920E3 are resettable surface-mount polymer PTC thermistors designed to protect low-voltage electronic circuits from overcurrent conditions. The six series cover package sizes from 0603 to 2920, with holding currents from 20mA to 5A and trip currents up to 10A.

Frequently Asked Questions

What is a polymer PTC thermistor?

A polymer positive temperature coefficient (PPTC) thermistor is a resettable overcurrent protection device. When excessive current flows, its resistance increases rapidly to limit the fault current. Once the fault is removed and the device cools, it returns to its normal low-resistance state.

When should you use a resettable PTC instead of a fuse?

Resettable PTC thermistors are commonly used where equipment may experience repeated overload or short-circuit conditions and replacing a conventional fuse would be inconvenient. Typical applications include USB ports, battery-powered products, networking equipment, and industrial control systems.

Why is low resistance important in a PTC thermistor?

A lower resistance reduces the voltage drop across the protection device during normal operation. This helps minimise power loss while still allowing the device to trip quickly if an overcurrent fault occurs.