Surface-mount fuses rate to 100 A in a single device

source: Electronic products news

Ultra-high current rating Littelfuse SMD fuse eliminates need to use parallel fuses or large devices.

Circuit boards with high current demands, like blade servers, backplanes, and high-wattage power supplies, create challenges for developers incorporating circuit-protecting fuses. To use compact, surface-mount devices required the paralleling of multiple lower-current fuses or the use of larger, overcapacity industrial devices. The Nano2 881 series of fuses corrects the situation, offering ratings to 100 A in a 12.5 x 10 x 6.8-mm surface-mount device (SMD).

The 881 series devices are RoHS-compliant with robust operating characteristics. They have thermoplastic bodies that work in –55°C to 100°C operating environments, have cold resistance as low as 0.45 Ω, and exhibit a nominal voltage drop of under 85 mV. Their robust physical design also reduces their susceptibility to temperature cycling and vibration, enhancing system reliability.

The devices also have impressive electrical characteristics. With a 75-V operating voltage, they have a range of current ratings of 60 to 100 A. At 200% overload current, they interrupt within 60 s. With surge currents, they can protect against as much as 1,500 A without rupturing (interrupting rating).

Circuit boards handling high current while requiring high component density are candidates for use of the 881 series. Typical applications in the data center market include blade servers, server chassis, backplane boards, and line cards. Additional applications in the power system market include uninterruptible power supplies, base station power supplies, high-power battery systems, and power factor correction (PFC) in high-wattage power supplies.