81CNQ040S2

Overview

The SMC Diode Solutions 81CNQ040S2 is a Schottky rectifier diode array housed in the PRM2 package. It features a center tap configuration with one pair of common cathodes. The device supports a maximum repetitive reverse voltage of 40 V and an average rectified forward current of 80 A per leg. Operating junction temperatures range from -55°C to +175°C. Electrical characteristics include a typical forward voltage drop of 0.60 V at 40 A and 0.74 V at 80 A, measured at 25°C. Reverse leakage current is specified at 5 mA maximum at 25°C. Thermal resistance from junction to case is typically 0.85 °C/W per leg.

Feature Summary

• Center tap module design for efficient power conversion
• High purity, high temperature epoxy encapsulation for mechanical strength and moisture resistance
• Guard ring structure for enhanced ruggedness and long-term reliability
• Lead-free device construction with full wafer lot traceability

Applications

• Switching power supplies
• DC-DC converters
• Free-wheeling diodes
• Reverse battery protection circuits

Procurement Notes

Verify the ordering suffix 'S2' indicates pure tin terminal finish rather than lead-tin or nickel plating. Confirm the PRM2 package dimensions match the target PCB footprint. Ensure thermal management solutions account for the specified junction-to-case thermal resistance values under DC operation conditions.

Selection Notes

Select this component when a 40 V rating and 80 A continuous current capability are required in a low-profile through-hole package. The center tap topology suits bridgeless PFC or synchronous rectification applications. Evaluate thermal performance against the 0.85 °C/W junction-to-case resistance to determine heatsinking requirements for the intended duty cycle.

Part Context

This part belongs to the 81CNQ series of Schottky rectifiers manufactured by SMC Diode Solutions. The series includes variants with 35 V, 40 V, and 45 V ratings. All models share the same PRM2 family packages and utilize high-purity epoxy encapsulation. The series is designed for high-frequency operation and offers low forward voltage drops compared to standard PN junction rectifiers.

Replacement Considerations

Cross-reference with other 81CNQ040 variants such as 81CNQ040 (Nickel plated) or 81CNQ040S1 (PbSn dipped) if terminal finish compatibility differs. Verify that alternative manufacturers offer identical PRM2 mechanical footprints and equivalent 80 A / 40 V specifications before substitution.

FAQ

What does the 'S2' suffix indicate for the 81CNQ040S2?

The 'S2' suffix denotes that the device terminals have a pure tin dip finish.

What is the maximum operating junction temperature?

The maximum operating junction temperature is +175°C.

Is the 81CNQ040S2 a single diode or an array?

It is a diode array configured as one pair of common cathodes with a center tap.