Bourns Announces freeXpansion™ Technology for its Multifuse® Polymer PTC Resettable Fuses

RIVERSIDE, Calif., March 23, 2009

Bourns, Inc., a leading manufacturer and supplier of electronic components, today announced that the company has developed freeXpansion™, a new technology added to the company’s entire line of Multifuse® surface mount polymer positive temperature coefficient (PTC) resettable fuses. This new technology increases the performance of the fuse with the ability to handle higher currents and voltages, improves its resistance stability and allows for a smaller footprint. Due to its new freeXpansion technology, Bourns is able to introduce one of the smallest families of PTCs on the market with a size of 0603, designated the Bourns MF-FSMF Series. Bourns’ Multifuse surface mount devices manufactured using the freeXpansion process is designed to meet next-generation electronics smaller size and high current requirements. Multifuse devices are an optimal overcurrent circuit protection solution for broad range of equipment including products with USB 2.0, USB 3.0 and HDMI ports and in consumer electronics and automotive electronics applications.

Polymer PTC resettable fuses expand when an overcurrent event occurs and contracts when they reset. The freeXpansion technology allows the device to freely expand and contract without mechanical restrictions for more stable performance, extended product life and to be manufactured in a smaller size.

"Bourns Multifuse products with freeXpansion offer distinct competitive advantages for our customers enabling reliable circuit protection across a broader range of applications,” said Brian Ahearne, technical marketing manager for Bourns’ Multifuse products. “As more and more electronic products become portable with design space constraints, Bourns Multifuse devices match application requirements for a smaller package and the ability to handle higher currents and voltages helping our OEM customers protect their valuable circuits from overcurrent conditions.”

Bourns Multifuse devices act as critical circuit protection components by limiting dangerous current surges, such as short circuits in electrical equipment. These devices provide secure protection as they react to an over-current event by changing from a very low resistive state to a very high resistive state. This is also referred to as the positive temperature coefficient effect or PTC effect. Once the overcurrent surge has passed, the Multifuse device automatically resets to its low resistive state and allows the equipment to resume operation.

Pricing and Availability
Bourns’ line of surface mount Multifuse devices with new freeXpansion technology is available now. For complete model numbers and sizes, go to Bourns’ site at As a pricing reference, devices with freeXpansion are priced from $0.25-$0.35 in 6,000 piece quantities.

About Bourns

Bourns, Inc., is a leading manufacturer and supplier of position and speed sensors, circuit protection solutions, magnetic components, microelectronic modules, panel controls and resistive products. Headquartered in Riverside, California, USA, Bourns serves a broad range of markets, including automotive, industrial, consumer, communications, non-critical life support medical (low/medium risk), audio and various other market segments. Additional company and product information is available at

Bourns® and the Bourns logo are registered trademarks of Bourns, Inc. and may be used only with the permission of Bourns and proper acknowledgement. Other listed names and brands are trademarks or registered trademarks of their respective owners.

Bourns® products have not been designed for and are not intended for use in "lifesaving," "life-critical" or "life-sustaining" applications nor any other applications where failure or malfunction of the Bourns® product may result in personal injury or death. See Legal Disclaimer Notice

Agency Contact:
Annette Keller
Keller Communication
Company Contact:
David Scofield
Bourns, Inc.
(951) 781-5054