2.6 A hold, 12 V max — the LoRho PTC for tight board budgets
The Littelfuse 1206L260/12SLYR is a polymeric PTC resettable fuse from the POLY-FUSE LoRho series, designed to protect low-voltage DC power rails up to 12 V. Its 2.6 A hold current (Ih) means it carries that load continuously without tripping, while the 5 A trip current (It) defines the threshold where the device starts heating and switches to a high-resistance state within 4 seconds. The 50 A maximum fault current rating tells you it can safely interrupt a short circuit up to that level without rupturing — a key spec for designing the trace and pad geometry on the board.
Footprint and thermal — 1206 concave, 3 mOhm initial resistance
The concave termination style suits automated pick-and-place and reflow soldering. The initial resistance (Ri) is a low 3 mOhms minimum, which means minimal I²R loss at the 2.6 A hold current — about 20 mW of self-heating in the steady state. After a trip event, the post-trip resistance (R1) climbs to 55 mOhms maximum, so the circuit sees a higher impedance until the fault clears and the PTC cools.