Obsolete 3.5A slow-blow — the sourcing reality
The 1206SFS350F/32-2 is marked obsolete by Littelfuse. Sourcing now runs through independent surplus and broker channels.
What the ratings mean for the board
Rated 3.5 A at 32 V DC with a 50 A interrupting capacity at that voltage — this fuse clears a hard short on a 24 V or 12 V rail without rupturing the 1206 ceramic body, but it is not rated for AC line use. Slow-blow response (1.6 A²s melting I²t) means it tolerates inrush from a capacitive input or a motor start without nuisance opening, unlike a fast-acting fuse of the same current rating. DC cold resistance is 0.028 Ω — at 3.5 A the voltage drop is under 100 mV, so the fuse adds negligible loss in a low-voltage rail.
Package and temperature envelope
1206 (3216 metric) SMD footprint, surface-mount only. UL recognized — the agency mark confirms the interrupting rating and the time-current characteristic are third-party verified, not just manufacturer-claimed.