Active production, sealed-reel surplus angle
The 0603L025YR is an active-production Littelfuse POLY-FUSE polymeric PTC resettable fuse. For surplus-lot buyers, this means sealed reels with consistent date-codes are the norm — no end-of-life scramble, no mixed-date auction lots that smell like repackaged returns.
Hold current and trip performance
Rated at 250 mA hold current (Ih) with a 550 mA trip current (It) — the fuse stays latched below 250 mA and trips within 80 ms when the fault exceeds the trip threshold. The initial resistance floor is 500 mOhms, rising to a 3 Ohm max post-trip, which limits voltage drop during normal operation and resets to a higher resistance after a fault clears.
Fault handling and approvals
Handles up to 40 A fault current at 9 V max — the voltage ceiling is low, so this part is best suited for low-voltage DC rail protection (USB, battery, or logic supplies). cURus and TUV agency approvals mean it passes UL and IEC-based safety tests for polymeric PTCs, covering the regulatory gate for most equipment sold into North America and Europe.
Package and board-fit
Housed in a 0603 (1608 Metric) concave surface-mount package, 1.60 mm x 0.80 mm footprint with a 0.75 mm max thickness. The concave termination profile suits standard reflow profiles and is compatible with tape-and-reel handling for high-volume pick-and-place.