The new K5V series switch integrates LED backlight, gold-plated reliability, and compact dust-proof design, using high-temperature resistant PAR material to achieve efficient SMT assembly.
On October 15, 2025, Rosemont Littelfuse, Illinois (NASDAQ: LFUS) is a diversified industrial technology manufacturing company committed to providing power for a sustainable, interconnected, and safer world. The company announced today the launch of the first K5V4 illuminated tactile switch that supports reflow soldering, has long stroke and single pole bi-directional (SPDT) function, expanding the K5V series of illuminated tactile switch products. The products include Gull Wing (GH) and 2.1mm Pin Dip Solder Paste (PIP) versions, both of which are compatible with reflow soldering.
The new K5V4 switch is made of high-temperature PAR (polyarylester) material, with a thermal deformation threshold of 250 ℃, making it very suitable for manufacturers transitioning from wave soldering to reflow soldering processes. This switch does not require a silicone sleeve or special treatment, achieving direct SMT assembly for the first time, thereby reducing production costs, increasing output, improving final product quality, while maintaining durability and tactile performance.
Jeremy Hebras, Vice President of Switch and Sensor Engineering at Littelfuse, said: "This new K5V4 switch is designed to meet the needs of today's compact electronic systems, where space efficiency, reliability, and user interface feedback are crucial. The K5V switch product series is designed to meet customers' unique device architecture requirements, where the motherboard and components are positioned at a 90 ° angle to the front panel. Combining long travel, sharp touch, and backlight function, the K5V is an ideal choice for precise device control, especially in situations where accidental driving or lack of immediate user feedback is required。
Main functions and features:
• Compatible with PAR material for reflow soldering, no need for casing;
SPDT contact configuration, providing normally open and normally closed options;
• Sharp tactile response, audible clicking sound, with 4N operating force;
• Integrated high brightness LED, with multiple colors and dual colors to choose from;
•Compact dust-proof design, capable of reliable operation within dense circuit boards;
•Gold plated dome contacts with excellent long-term contact performance;
•Provide SMT (GH) and THT (PIP) versions for flexible design.
Market and Application:
• Data centers and servers: system control and diagnostic interface buttons;
• Network infrastructure: reset and feedback switches for routers and telecommunications equipment;
•Industrial equipment: control panel interface, safety reset point, and signal input;
•Professional audio/video system: provides tactile response for mixers, distribution boards, and low light interfaces.
Littelfuse's first long stroke SMT package using reflow soldering SPDT、 The illuminated tactile switch fills a key gap in the market. In contrast, other similar products on the market typically require wave soldering, which increases the complexity and cost of assembly processes. The K5V4 series combines excellent ergonomics, visual feedback, and manufacturability in a compact and robust solution.
This expansion strengthens Littelfuse's commitment to driving the development of tactile switch technology, providing OEMs with high-performance human-machine interface (HMI) components optimized for modern production environments.
Supply situation
K5V tactile switches are available in tape packaging, with minimum order quantities ranging from 1000 to 2000. Samples can be obtained through authorized Littelfuse distributors worldwide. To learn about the list of authorized Littelfuse distributors, please visit Littelfuse.com.
