Obsolete — sourcing reality for the 1206SFS300F/32-2
The Littelfuse 1206SFS300F/32-2 is listed as Obsolete by the manufacturer. This part is available through independent surplus and broker channels.
3 A slow blow, 32 VDC — what the ratings mean for the BOM
Rated 3 A continuous at 32 VDC with a 50 A breaking capacity at that voltage — the fuse clears a fault up to 50 A without rupturing the 1206 ceramic body. Below that threshold it opens safely; above it the arc may not extinguish inside the package. Slow-blow response means the element absorbs inrush current pulses without nuisance opening — a 1.2 A²s melting I²t gives roughly 0.13 seconds to open at 3 A, scaling inversely with the square of the fault current. This suits capacitive input loads or motor start-up where the peak exceeds the steady-state rating for tens of milliseconds. DC cold resistance is 0.034 ohms — at 3 A the self-heating I²R loss is 0.3 W, negligible in still air but worth a check if the fuse is packed between heat-sinking traces on a dense board.
UL recognized, 1206 SMD — board-fit and compliance
UL recognized — the fuse carries UL listing for the 3 A / 32 VDC / 50 A interrupting rating, which is the primary acceptance mark for North American equipment. The 0.97 mm height clears most conformal-coat thicknesses and under-fill gaps. Tape & Reel packaging suits automated pick-and-place.