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Bourns' Latest Miniature Resettable Thermal Cutoff (TCO) Devices Feature Higher Current-Carrying Capabilities to Protect Today's High Energy Density Batteries

With its higher current capabilities and ultra-small size, Bourns® Model NX Series enables customers to shrink their product size and still maintain an elevated level of overtemperature protection

RIVERSIDE, Calif., March 12, 2024 - Bourns, Inc., a leading manufacturer and supplier of electronic components for power, protection, and sensing solutions, today announced its latest miniature resettable thermal cutoff (TCO) device series, also known as mini-breakers, that are designed to control abnormal, excessive current virtually instantaneously, up to rated limits. The Model NX Series offers higher current-carrying capabilities combined with a very low-profile package at a height of 0.94 mm and body width of 2.8 mm. These features make this series an ideal overtemperature and overcurrent protection solution for lithium polymer and prismatic cells in high energy density, smaller batteries such as next-generation notebook PC and tablet battery cells, as well as handheld and wearable electronics.

"While our new Model NX Series has the same footprint as our Model NR series, it can carry 40 percent more current. This is the result of numerous design advancements including the use of new high conductivity electrode materials," said Brian Ahearne, Vice President of Products and Technology at Bourns Thermal & Precision Division. "These features enable customers to shrink the size of their product and still maintain an elevated level of overtemperature and overcurrent protection that enhances their product reliability and safety."

The new Model NX Series has current capabilities from 12 A to 20 A at 60 °C and is available with or without welding projections. Providing design flexibility for a wide range of application environments, these TCO devices are available with four trip temperature options of 77 °C, 82 °C, 85 °C and 90 °C - all of which operate within a ±5 °C tolerance. The Model NX Series also is designed with a high-rated corrosion resistant bimetal mechanism that delivers enhanced endurance in humid environments compared to standard TCO devices.

Bourns® Model NX Series is available now and is RoHS* compliant, halogen free** and UL/TÜV recognized. For more detailed product information, please see:

*RoHS Directive 2015/863, Mar 31, 2015 and Annex.

**Bourns considers a product to be "halogen free" if (a) the Bromine (Br) content is 900 ppm or less; (b) the Chlorine (Cl) content is 900 ppm or less; and (c) the total Bromine (Br) and Chlorine (Cl) content is 1500 ppm or less.

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