KRL Series Resistors

Susumu KRL series resistors are low-resistance, current-sensing chip resistors. The face-down structure, large resistive element, and specially formulated heat-conductive adhesive all contribute to the superb heat dissipation capability. The typical thermal resistivity of the KRL series is +19°C/W, a value less than half of that offered by other products on the market. This allows KRL to offer smaller sizes at the same power rating as compared to other current sensors. Its structure also contributes to unmatched tolerance to temperature cycling, maintaining the integrity of the solder joints without cracking after 3,000 temperature cycles of -45°C to +125°C.

The KRL series has been officially listed by NASA under its NEPP (NASA electronic parts and packaging) program as an industry-leading parts manufacturer (ILPM) and recognized as an established COTS part. This recognition follows the earlier qualification of the RG series, marking another milestone in the contribution from Susumu to space-grade component reliability.

The ILPM and established COTS designation are granted based on the NESC technical assessment phase II report from NASA, “Recommendations on the Use of Commercial‑Off‑The‑Shelf (COTS) Electrical, Electronic, and Electromechanical (EEE) Parts for NASA Missions.” Manufacturers included in the ILPM list must demonstrate high-volume production, stable processes, 100% electrical testing at typical conditions, statistical process control (SPC), consistent yield trends, and robust reliability tracking.

The KRL series meets these stringent criteria and earned official placement on the NASA ILPM and established COTS parts list. This recognition underscores the commitment to delivering high‑quality, high‑reliability components suitable for spaceflight applications and opens opportunities for adoption in aerospace and related industries.