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Y78B42120FP
Y78B42120FP Tactile Switch by LITTELFUSE / C&K COMPONENTS
Part Number: Y78B42120FPDownload Datasheet
Product Features
Microminiature SMT top actuated switch designed for high durability and reliability
Excellent tactile feedback with multiple actuation force options
Ultra-low current capabilities suitable for sensitive electronic applications
IP40 rated for protection against dust and limited ingress
Small footprint ideal for compact electronic designs
Electrical Characteristics
Parameter
Silver
Gold
Maximum Power
1 VA
0.2 VA
Maximum Voltage
32 VDC
32 VDC
Minimum Voltage
20 mVDC
20 mVDC
Maximum Current
50 mA
10 mA
Minimum Current
1 mA¹
1 mA¹
Dielectric Strength
≥ 250 Vrms
Contact Resistance
≤ 100 mΩ
Insulation Resistance
≥ 1 GΩ
Bounce Time
≤ 3 ms
Environmental Characteristics
Parameter
Silver
Gold
Operating Temperature
-40°C to 85°C
-40°C to 125°C
Storage Temperature
-55°C to 85°C
-55°C to 125°C
Mechanical Characteristics
Type
Operation Force (N)
Operation Cycles
Travel (mm)
KMR421 LFS, KMR421 ULC LFS
2.0 (200 g)
100,000
0.25 mm ± 0.1
KMR443 LFG, KMR443 ULC LFG
4.0 (400 g)
100,000
0.30 mm ± 0.1
Additional Details
Suitable for industrial, medical, and automotive applications
Designed for harsh environments with long-lasting performance
Available with ground pin (G) or no ground pin (NG) options
Disclaimer
This datasheet does not provide enough information for applications that require a certain level of quality or safety such as automotive, medical systems, or safety equipment. Please contact customer service for the contractual specification package.
For more detailed specifications and custom options, please refer to the full datasheet .
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{"id":10027967742269,"title":"Y78B42120FP","handle":"y78b42120fp","description":"\u003ch3\u003eY78B42120FP Tactile Switch by LITTELFUSE \/ C\u0026amp;K COMPONENTS\u003c\/h3\u003e\n\u003cp\u003ePart Number: Y78B42120FP\u003cbr\u003e\nManufacturer: LITTELFUSE \/ C\u0026amp;K COMPONENTS\u003cbr\u003e\nCountry of Origin: France (FR)\u003cbr\u003e\nUnit of Measure: Each (EA)\u003cbr\u003e\nECCN: EAR99\u003cbr\u003e\nPackage Type: Not specified\u003cbr\u003e\nDatasheet: \u003ca href=\"https:\/\/ckswitches.com\/media\/1480\/kmr4.pdf\" target=\"_blank\"\u003eDownload Datasheet\u003c\/a\u003e\u003c\/p\u003e\n\n\u003ch3\u003eProduct Features\u003c\/h3\u003e\n\u003cul\u003e\n \u003cli\u003eMicrominiature SMT top actuated switch designed for high durability and reliability\u003c\/li\u003e\n \u003cli\u003eExcellent tactile feedback with multiple actuation force options\u003c\/li\u003e\n \u003cli\u003eUltra-low current capabilities suitable for sensitive electronic applications\u003c\/li\u003e\n \u003cli\u003eIP40 rated for protection against dust and limited ingress\u003c\/li\u003e\n \u003cli\u003eSmall footprint ideal for compact electronic designs\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eElectrical Characteristics\u003c\/h3\u003e\n\u003ctable border=\"1\" cellpadding=\"5\" cellspacing=\"0\"\u003e\n \u003ctr\u003e\n \u003cth\u003eParameter\u003c\/th\u003e\n \u003cth\u003eSilver\u003c\/th\u003e\n \u003cth\u003eGold\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMaximum Power\u003c\/td\u003e\n \u003ctd\u003e1 VA\u003c\/td\u003e\n \u003ctd\u003e0.2 VA\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMaximum Voltage\u003c\/td\u003e\n \u003ctd\u003e32 VDC\u003c\/td\u003e\n \u003ctd\u003e32 VDC\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMinimum Voltage\u003c\/td\u003e\n \u003ctd\u003e20 mVDC\u003c\/td\u003e\n \u003ctd\u003e20 mVDC\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMaximum Current\u003c\/td\u003e\n \u003ctd\u003e50 mA\u003c\/td\u003e\n \u003ctd\u003e10 mA\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMinimum Current\u003c\/td\u003e\n \u003ctd\u003e1 mA¹\u003c\/td\u003e\n \u003ctd\u003e1 mA¹\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eDielectric Strength\u003c\/td\u003e\n \u003ctd colspan=\"2\"\u003e≥ 250 Vrms\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eContact Resistance\u003c\/td\u003e\n \u003ctd colspan=\"2\"\u003e≤ 100 mΩ\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eInsulation Resistance\u003c\/td\u003e\n \u003ctd colspan=\"2\"\u003e≥ 1 GΩ\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eBounce Time\u003c\/td\u003e\n \u003ctd colspan=\"2\"\u003e≤ 3 ms\u003c\/td\u003e\n \u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eEnvironmental Characteristics\u003c\/h3\u003e\n\u003ctable border=\"1\" cellpadding=\"5\" cellspacing=\"0\"\u003e\n \u003ctr\u003e\n \u003cth\u003eParameter\u003c\/th\u003e\n \u003cth\u003eSilver\u003c\/th\u003e\n \u003cth\u003eGold\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eOperating Temperature\u003c\/td\u003e\n \u003ctd\u003e-40°C to 85°C\u003c\/td\u003e\n \u003ctd\u003e-40°C to 125°C\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eStorage Temperature\u003c\/td\u003e\n \u003ctd\u003e-55°C to 85°C\u003c\/td\u003e\n \u003ctd\u003e-55°C to 125°C\u003c\/td\u003e\n \u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eMechanical Characteristics\u003c\/h3\u003e\n\u003ctable border=\"1\" cellpadding=\"5\" cellspacing=\"0\"\u003e\n \u003ctr\u003e\n \u003cth\u003eType\u003c\/th\u003e\n \u003cth\u003eOperation Force (N)\u003c\/th\u003e\n \u003cth\u003eOperation Cycles\u003c\/th\u003e\n \u003cth\u003eTravel (mm)\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eKMR421 LFS, KMR421 ULC LFS\u003c\/td\u003e\n \u003ctd\u003e2.0 (200 g)\u003c\/td\u003e\n \u003ctd\u003e100,000\u003c\/td\u003e\n \u003ctd\u003e0.25 mm ± 0.1\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eKMR443 LFG, KMR443 ULC LFG\u003c\/td\u003e\n \u003ctd\u003e4.0 (400 g)\u003c\/td\u003e\n \u003ctd\u003e100,000\u003c\/td\u003e\n \u003ctd\u003e0.30 mm ± 0.1\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003c!-- Additional models can be added as needed --\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eAdditional Details\u003c\/h3\u003e\n\u003cul\u003e\n \u003cli\u003eSuitable for industrial, medical, and automotive applications\u003c\/li\u003e\n \u003cli\u003eDesigned for harsh environments with long-lasting performance\u003c\/li\u003e\n \u003cli\u003eAvailable with ground pin (G) or no ground pin (NG) options\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eDisclaimer\u003c\/h3\u003e\n\u003cp\u003eThis datasheet does not provide enough information for applications that require a certain level of quality or safety such as automotive, medical systems, or safety equipment. Please contact customer service for the contractual specification package.\u003c\/p\u003e\n\n\u003cp\u003eFor more detailed specifications and custom options, please refer to the \u003ca href=\"https:\/\/ckswitches.com\/media\/1480\/kmr4.pdf\" target=\"_blank\"\u003efull datasheet\u003c\/a\u003e.\u003c\/p\u003e\u003cbr\u003e","published_at":"2025-08-16T05:20:20+05:30","created_at":"2025-08-16T05:20:20+05:30","vendor":"Waldom Electonics","type":"","tags":["IMPORT_CSV","IMPORT_PT2","LITTE-CKCO","WLDM"],"price":3271,"price_min":3271,"price_max":3271,"available":true,"price_varies":false,"compare_at_price":null,"compare_at_price_min":0,"compare_at_price_max":0,"compare_at_price_varies":false,"variants":[{"id":50626367291709,"title":"Default Title","option1":"Default Title","option2":null,"option3":null,"sku":"Y78B42120FP","requires_shipping":true,"taxable":true,"featured_image":null,"available":true,"name":"Y78B42120FP","public_title":null,"options":["Default Title"],"price":3271,"weight":250,"compare_at_price":null,"inventory_management":"shopify","barcode":"Y78B42120FP","requires_selling_plan":false,"selling_plan_allocations":[]}],"images":["\/\/thinkrobotics.com\/cdn\/shop\/files\/11132744.png?v=1755301823"],"featured_image":"\/\/thinkrobotics.com\/cdn\/shop\/files\/11132744.png?v=1755301823","options":["Title"],"media":[{"alt":null,"id":45862574129469,"position":1,"preview_image":{"aspect_ratio":1.0,"height":400,"width":400,"src":"\/\/thinkrobotics.com\/cdn\/shop\/files\/11132744.png?v=1755301823"},"aspect_ratio":1.0,"height":400,"media_type":"image","src":"\/\/thinkrobotics.com\/cdn\/shop\/files\/11132744.png?v=1755301823","width":400}],"requires_selling_plan":false,"selling_plan_groups":[],"content":"\u003ch3\u003eY78B42120FP Tactile Switch by LITTELFUSE \/ C\u0026amp;K COMPONENTS\u003c\/h3\u003e\n\u003cp\u003ePart Number: Y78B42120FP\u003cbr\u003e\nManufacturer: LITTELFUSE \/ C\u0026amp;K COMPONENTS\u003cbr\u003e\nCountry of Origin: France (FR)\u003cbr\u003e\nUnit of Measure: Each (EA)\u003cbr\u003e\nECCN: EAR99\u003cbr\u003e\nPackage Type: Not specified\u003cbr\u003e\nDatasheet: \u003ca href=\"https:\/\/ckswitches.com\/media\/1480\/kmr4.pdf\" target=\"_blank\"\u003eDownload Datasheet\u003c\/a\u003e\u003c\/p\u003e\n\n\u003ch3\u003eProduct Features\u003c\/h3\u003e\n\u003cul\u003e\n \u003cli\u003eMicrominiature SMT top actuated switch designed for high durability and reliability\u003c\/li\u003e\n \u003cli\u003eExcellent tactile feedback with multiple actuation force options\u003c\/li\u003e\n \u003cli\u003eUltra-low current capabilities suitable for sensitive electronic applications\u003c\/li\u003e\n \u003cli\u003eIP40 rated for protection against dust and limited ingress\u003c\/li\u003e\n \u003cli\u003eSmall footprint ideal for compact electronic designs\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eElectrical Characteristics\u003c\/h3\u003e\n\u003ctable border=\"1\" cellpadding=\"5\" cellspacing=\"0\"\u003e\n \u003ctr\u003e\n \u003cth\u003eParameter\u003c\/th\u003e\n \u003cth\u003eSilver\u003c\/th\u003e\n \u003cth\u003eGold\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMaximum Power\u003c\/td\u003e\n \u003ctd\u003e1 VA\u003c\/td\u003e\n \u003ctd\u003e0.2 VA\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMaximum Voltage\u003c\/td\u003e\n \u003ctd\u003e32 VDC\u003c\/td\u003e\n \u003ctd\u003e32 VDC\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMinimum Voltage\u003c\/td\u003e\n \u003ctd\u003e20 mVDC\u003c\/td\u003e\n \u003ctd\u003e20 mVDC\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMaximum Current\u003c\/td\u003e\n \u003ctd\u003e50 mA\u003c\/td\u003e\n \u003ctd\u003e10 mA\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMinimum Current\u003c\/td\u003e\n \u003ctd\u003e1 mA¹\u003c\/td\u003e\n \u003ctd\u003e1 mA¹\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eDielectric Strength\u003c\/td\u003e\n \u003ctd colspan=\"2\"\u003e≥ 250 Vrms\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eContact Resistance\u003c\/td\u003e\n \u003ctd colspan=\"2\"\u003e≤ 100 mΩ\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eInsulation Resistance\u003c\/td\u003e\n \u003ctd colspan=\"2\"\u003e≥ 1 GΩ\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eBounce Time\u003c\/td\u003e\n \u003ctd colspan=\"2\"\u003e≤ 3 ms\u003c\/td\u003e\n \u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eEnvironmental Characteristics\u003c\/h3\u003e\n\u003ctable border=\"1\" cellpadding=\"5\" cellspacing=\"0\"\u003e\n \u003ctr\u003e\n \u003cth\u003eParameter\u003c\/th\u003e\n \u003cth\u003eSilver\u003c\/th\u003e\n \u003cth\u003eGold\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eOperating Temperature\u003c\/td\u003e\n \u003ctd\u003e-40°C to 85°C\u003c\/td\u003e\n \u003ctd\u003e-40°C to 125°C\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eStorage Temperature\u003c\/td\u003e\n \u003ctd\u003e-55°C to 85°C\u003c\/td\u003e\n \u003ctd\u003e-55°C to 125°C\u003c\/td\u003e\n \u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eMechanical Characteristics\u003c\/h3\u003e\n\u003ctable border=\"1\" cellpadding=\"5\" cellspacing=\"0\"\u003e\n \u003ctr\u003e\n \u003cth\u003eType\u003c\/th\u003e\n \u003cth\u003eOperation Force (N)\u003c\/th\u003e\n \u003cth\u003eOperation Cycles\u003c\/th\u003e\n \u003cth\u003eTravel (mm)\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eKMR421 LFS, KMR421 ULC LFS\u003c\/td\u003e\n \u003ctd\u003e2.0 (200 g)\u003c\/td\u003e\n \u003ctd\u003e100,000\u003c\/td\u003e\n \u003ctd\u003e0.25 mm ± 0.1\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eKMR443 LFG, KMR443 ULC LFG\u003c\/td\u003e\n \u003ctd\u003e4.0 (400 g)\u003c\/td\u003e\n \u003ctd\u003e100,000\u003c\/td\u003e\n \u003ctd\u003e0.30 mm ± 0.1\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003c!-- Additional models can be added as needed --\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eAdditional Details\u003c\/h3\u003e\n\u003cul\u003e\n \u003cli\u003eSuitable for industrial, medical, and automotive applications\u003c\/li\u003e\n \u003cli\u003eDesigned for harsh environments with long-lasting performance\u003c\/li\u003e\n \u003cli\u003eAvailable with ground pin (G) or no ground pin (NG) options\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eDisclaimer\u003c\/h3\u003e\n\u003cp\u003eThis datasheet does not provide enough information for applications that require a certain level of quality or safety such as automotive, medical systems, or safety equipment. Please contact customer service for the contractual specification package.\u003c\/p\u003e\n\n\u003cp\u003eFor more detailed specifications and custom options, please refer to the \u003ca href=\"https:\/\/ckswitches.com\/media\/1480\/kmr4.pdf\" target=\"_blank\"\u003efull datasheet\u003c\/a\u003e.\u003c\/p\u003e\u003cbr\u003e"}
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