KSC241GLFS

1. Overview

The KSC241GLFS is a sealed surface-mount (SMD) tactile switch from C&K (now part of Littelfuse), belonging to the KSC Series of Sealed Tact Switches for SMT. The part number decodes precisely from the C&K ordering guide: KSC (series) + 2 (soft silicone actuator, 3.5mm height) + 4 (operating force code: 3N/3.5N, i.e. 300–350gf) + 1 (silver contact material, standard life) + G (gull-wing termination) + LFS (lead-free compatible, silver plated). The switch body measures 6.2 × 6.2mm and is rated IP67 (dust-tight, waterproof immersion), making it suitable for harsh-environment electronics. C&K was historically a French brand; the product is positioned as an industrial-grade sealed tactile for SMT reflow assembly.

2. User Sentiment

No forum reviews or user opinion data were found in the source corpus for this specific part number. The switch is a standard industrial SMD tactile from a well-regarded manufacturer, widely stocked by major global distributors (DigiKey, Mouser, Arrow, Farnell, TTI, Future Electronics, LCSC, JLCPCB), which indicates strong market acceptance. Its IP67 rating and AEC-Q200 automotive qualification are commonly cited as key differentiators in distributor descriptions. The JLCPCB/LCSC listing (part C221730) indicates broad adoption in the PCB prototyping and small-run manufacturing community.

3. Real-World Applications

C&K's own datasheet lists target applications as: automotive, cellular phones, industrial electronics, and network infrastructure/IT. The IP67 sealing makes it particularly suited for outdoor panels, handheld test equipment, marine controls, and automotive HMI where moisture ingress is a concern. The AEC-Q200 automotive qualification (noted in the Button Index catalog entry) confirms suitability for in-vehicle environments. The soft silicone round-button actuator (code "2") provides a distinct tactile feel suitable for operator-facing controls.

4. Technical Specifications

• Type: Sealed SMD tactile switch, momentary action (off-(on))
• Series: KSC2 (6.2 × 6.2mm body, soft actuator 3.5mm height)
• Mount: Surface Mount (SMT), gull-wing (G) leads — NOT through-hole
• Contact Form: SPST-NO (1 make contact)
• Actuator: Soft silicone round button, 3.5mm height off PCB, white color
• Operating Force: 3N / 3.5N (300–350gf) min/max per datasheet mechanical table for KSC241; nominal ~3.5N per distributor listings
• Switch Travel: 0.5 ± 0.2mm
• Electrical Rating (silver): 50mA max current, 32VDC max voltage, 1VA max power
• Contact Resistance: < 100mΩ
• Insulation Resistance: > 10⁹ Ω (at 100V)
• Dielectric Strength: 250V (50Hz, 1 min)
• Bounce Time: < 1ms
• Mechanical Life: 300,000 cycles (silver contact, standard life, code "1")
• IP Rating: IP67 (dust-tight, waterproof to 1m immersion)
• Operating Temperature: −40°C to +85°C
• Storage Temperature: −55°C to +85°C
• Termination: Gull-wing (G), silver-plated over nickel barrier
• Packaging: 2,000 pcs/reel, tape & reel per EIA RS481
• RoHS: Yes — LFS suffix confirms lead-free compatible, silver plated

5. Ordering & Compatibility

Available from DigiKey (part KSC241G-LFS, ~$0.60/1qty, ~$0.30 at volume), Mouser (KSC241G-LFS), Arrow, Newark (95W3279), Farnell (2320035), LCSC (C221730, ~$0.29), and TTI. The part is also sold under the Littelfuse brand following C&K's acquisition. JLCPCB lists it as C221730 for SMT assembly. Related variants within the KSC2 series include KSC221J (500kc silver long life), KSC222J (1M cycles gold), and KSC251J (higher force). The base non-RoHS variant is KSC241G (without LFS suffix). The "L" (long-life silver) or gold contact variants can be specified by changing position 3 of the part code.

6. Known Issues

DATA QUALITY FLAG: The Button Index catalog entry for product 297 lists actuation force as 200gf and mechanical life as 1,000,000 cycles — both are incorrect for this part. The C&K datasheet and all major distributors (DigiKey, element14, TME, Jotrin, ADatasheet, IBS Electronics) consistently report 300–350gf operating force and 300,000 cycle life for the KSC241 (silver, standard life) variant. The 1M cycle figure belongs to the KSC222J (gold, long life) or KSC422J variants. The catalog entry should be corrected: force = 300–350gf (3N–3.5N), life = 300,000 cycles. Additionally, some Mouser locale listings erroneously show "1A" current rating; the datasheet specifies 50mA max for silver contacts.