1.5 A slow-blow in 1206 — where this SFS fuse fits
The Littelfuse 1206SFS150F/63-2 is a 1.5 A slow-blow surface-mount fuse in the SFS series, packaged in the 1206 (3216 Metric) footprint. Slow-blow response means it tolerates brief inrush current pulses — motor starts, capacitor charging, hot-swap transients — without nuisance opening on a 1.5 A load line. Rated 63 V DC with a breaking capacity of 50 A at that voltage, it safely clears a fault up to 50 A in a 63 V rail without arc re-strike. The 0.23 melting I²t figure tells you the energy it can absorb before opening — match this to your inrush pulse I²t budget to confirm the fuse holds during start-up. DC cold resistance is 0.15 ohms, which at 1.5 A gives a 225 mV voltage drop across the fuse at steady state — factor this into the rail margin for the downstream circuitry.
Obsolete — sourcing this SFS fuse today
Littelfuse lists the 1206SFS150F/63-2 as obsolete. UL recognition is the key approval — this fuse carries UL certification for the 63 V DC / 50 A interrupting rating, which is the same standard most North American equipment-level safety certifications reference.