Hold current, voltage, and the trip decision
The 1206L005/30WR is a Littelfuse POLY-FUSE polymeric PTC resettable fuse in the 1206L series. Its 50 mA hold current (Ih) at 60 VDC max defines the steady-state operating envelope — below that current the device stays low-resistance; above it, the polymer heats and the resistance jumps, protecting the downstream circuit. Trip time is 1.5 seconds at fault current, with a post-trip resistance ceiling of 20 Ohms. The AEC-Q200 qualification confirms it has passed the stress tests for automotive-grade passive components — thermal shock, vibration, and bias humidity.
Surface-mount reflow assembly; the concave body allows visual inspection of the solder fillet on the terminations.
Approvals and compliance
Safety-agency approvals include cURus and TUV, covering North American and European equipment certification requirements. The AEC-Q200 rating means it is qualified for automotive electronics supply chains.