Hold current and trip behaviour
The 1206L075WR is a polymeric PTC resettable fuse from the POLY-FUSE 1206L series, rated for 750 mA hold current at 8V maximum. That hold current is the continuous DC current it passes without tripping at 25°C ambient — size the circuit so the normal operating current stays below this, not at it, to avoid nuisance trips near the thermal threshold. When a fault drives the current above the trip level, the device switches to a high-resistance state in typically 200 ms. After the fault clears and power is removed, it resets — no fuse replacement needed.
Interrupt rating and approvals
The device can interrupt fault currents up to 100 A at the rated 8V — this is the maximum short-circuit current it can safely clear without rupturing. For a low-voltage rail (5V or 3.3V USB, battery-protected lines), 100 A covers most realistic fault scenarios in portable or embedded gear. Safety agency approvals include cURus and TUV, which means the part is accepted for North American and European equipment-level safety certification without additional component-level testing.
Obsolete — what that means for procurement
Littelfuse lists the 1206L075WR as obsolete. For existing BOM lines that specify this exact part, supply is through independent distribution channels — quantities are confirmed at RFQ, and the parts are sourced as available surplus or new-old-stock inventory.