62 mA fast-blow SMD fuse for secondary-side protection
The Littelfuse 0451.062MRSN is a 62 mA, 125 VAC fast-blow SMD fuse from the NANO²® 451 series, housed in a compact 2-SMD square end block package measuring 6.10 mm x 2.69 mm x 2.69 mm. With a breaking capacity of 50 A at rated voltage, it safely interrupts overcurrent faults up to that level without rupturing, making it suitable for secondary-side protection in power supplies, battery management circuits, and low-current DC/DC converter rails.
What the ratings mean for your BOM fit
The 62 mA current rating is the continuous current the fuse carries without opening — budget a 20–25 % derating margin below the circuit's normal operating current to avoid nuisance blowing at elevated ambient temperatures. The 125 VAC voltage rating covers most secondary-side rails in off-line supplies; the fast-blow response time means it clears quickly on short-circuit faults, but it may nuisance-open on moderate inrush pulses that exceed the melting I²t of 0.00019 A²s.
Lifecycle and supply posture
Approved by CSA and UR (UL Recognized), the fuse meets North American safety agency requirements for recognized component use in end equipment.