NANO2® Fast-Acting Subminiature Surface Mount Fuses SMALLEST AC SMT FUSES 125/250vac Surface Mount AC Fuses for Compact Applications 470 & 476 Series Smallest 125VAC fuse (470 Series with 1206 footprint) and 250VAC fuse (476 Series with 2410 footprint) to occupy less board space With a 1206 footprint, the 470 Series is the smallest 125VACrated fast-acting fuse in the Littelfuse SMT fuse portfolio. This series exhibits high breaking capacity with unparalleled surge tolerance. It’s suitable for protecting compact applications against overload conditions. The 476 Series is a family of 250VAC-rated surface mountable fuses in a very small 2410 footprint. It is the smallest fuse with this high voltage rating from the Littelfuse SMT fuse portfolio. It’s designed mainly to serve as primary side circuit protection for compact applications with high voltage requirements. Applications • • • • • • LED Lighting LCD/LED TVs Notebooks/PCs White Goods Gaming Consoles Power Supply Units DataSheet 470 Series Samples 470 Series Design Guide DataSheet 476 Series Samples 476 Series Design Guide NANO2® Fast-Acting Subminiature Surface Mount Fuses The smallest 125VAC- and 250VAC-rated SMT fuses with 1206 and 2410 footprints Features Benefits • Surface Mount Type AC fuse • Smallest footprint • SMT is the future trend for compact applications with space constraints; it also enables higher speed and yield in manufacturing processes • Occupies less board space • Suitable for high temperature applications such as LED lighting • Withstands surge from AC power line and keeps LED light bulb/tube working continuously 470 Series • 470 Series – 1206 • 476 Series – 2410 • High operating temperature at 125°C • Surge Immunity Capability 476 Series • 470 Series – US: ENERGY STAR® 1 (1.5A and above ampere rating only) • 476 Series – Global: IEC 61000-4-5 2 ed. (3A and above ampere rating only) • RoHS compliant and halogen-free SMALLEST 470 vs 476 Comparison 125/250VAC Voltage 125Vac 250Vac Current 0.5A~2A 1A~15A Footprint 1206 2410 Interrupting 50A 100A AC SMT FUSES AC/DC Board Surface Mount Fuses (Power Supply & Driver) Surge Withstanding Operating Temperature LED Board (All SMT Components) MOV A fuse with adequate I t rating is necessary to pass ENERGY STAR® ring-wave tests according to IEEE C.62.41.2 A metal oxide varistor (MOV) can help protect the LED bulb from overvoltage surges and ring-wave effectes by clamping short-duration voltage impulses. AC Input EMI Filter TVS Diode High Voltage DC Fuse Line Rectifier A TVS Diode on the dc side can be used to protect against transients before entry into converter circuit. -55°C to 125°C -55°C to 125°C Osc. N PTC A positive temperature coefficient resistor can help protect LEDs from over-current and over-temperature. PLED Open circuit LED protection device LEDs DC-DC Converter L Iso / Step Down G Constant Current LED String Driver TVS Diode Controller / Opto Couplers 1 IEC61000-4-5 2 ed., Energy Star®, ring CombinationWave wave, 2.5kV (1.5A rating 500V/250A (3A rating and and above) and above) The 476 Series is the smallest SMT fuse with 250V voltage rating offered in the Littelfuse SMT fuse portfolio. It is designed to serve as the primary side circuit protection for compact devices with high voltage requirement. Indoor LED luminaire circuit 2 476 Series The 470 Series is designed to provide circuit protection for compact applications or as direct replacement to the standard 2410 Fuses. The platform itself is a breakthrough, eliminating the use of internal solders, which makes it 100% lead-free. AC LED Board Example of a 470 Series Fuse used in an LED Bulb AC Line Fuse 470 Series Transient protection for energy let through to the LED circuit ENERGY STAR® is a registered trademark for the Department of Energy © 2015 Littelfuse • 470 & 476 Series NANO2® Fast-Acting Subminiature Surface Mount Fuse littelfuse.com