Obsolete — sourcing through independent channels
Littelfuse has marked the 0603SFV400F/32-2 as obsolete. Availability and current pricing are quoted to order.
4 A fast-blow in a 0603 footprint — what the ratings mean for fit
Rated 4 A at 32 V DC with a fast-blow response. The 35 A breaking capacity at rated voltage means the fuse can safely interrupt a fault current up to 35 A without rupturing — adequate for low-voltage DC rails where the prospective short-circuit current stays below that ceiling. Melting I²t of 1.15 and a DC cold resistance of 0.023 Ohms define the inrush energy the fuse absorbs before opening. A downstream capacitor bank that draws a surge above this I²t will nuisance-blow the fuse — pre-charge or a slow-blow alternative may be needed. The 0603 (1608 metric) package is a standard surface-mount footprint.
UL recognition and compliance documentation
The fuse carries UL recognition, which certifies the device meets UL 248-14 for supplemental overcurrent protection. RoHS and REACH compliance documentation is available from Littelfuse upon request.