LD431850

Overview

The Powerex LD431850 is a POW-R-BLOK Dual SCR Isolated Module rated for 1800V and 500A average forward current. It features electrically isolated heatsinking via an aluminum nitride isolator, enabling direct mounting on common heatsinks without additional insulation components. The module supports up to 900A RMS forward current and includes compression bonded elements with a metal baseplate for low thermal impedance. Key electrical parameters include a repetitive peak blocking voltage of 1800V, a non-repetitive peak blocking voltage of 1900V, and a junction-to-case thermal resistance of 0.0650°C/W per junction. It operates within a temperature range of -40°C to +130°C.

Feature Summary

• Electrically isolated heatsinking design eliminates the need for separate insulating components
• Compression bonded elements ensure robust mechanical integrity and thermal performance
• Aluminum nitride isolator provides high dielectric strength between terminals and baseplate
• UL recognized certification simplifies compliance for industrial power applications

Applications

• Bridge circuits requiring phase control
• AC and DC motor drives
• Battery supplies
• Power supplies
• Large IGBT circuit front ends

Procurement Notes

Verify the complete eight-digit part number LD431850 against official datasheets before ordering. Confirm that the required voltage and current ratings align with specific application demands. Ensure mounting hardware meets the specified torque requirements for M6 and M10 screws to maintain proper thermal contact and electrical isolation integrity during installation.

Selection Notes

Select this module for high-power phase control applications where electrical isolation from the heatsink is mandatory. Consider the 1800V rating and 500A average current capacity when designing systems. Evaluate the thermal management requirements based on the provided junction-to-case thermal resistance and maximum allowable case temperature curves for sinusoidal or rectangular waveforms.

Part Context

The LD431850 belongs to the POW-R-BLOK family of dual SCR isolated modules manufactured by Powerex. This series is engineered for heavy-duty industrial environments, offering a compact solution for high-current switching. Similar models in the lineup vary primarily in voltage and current ratings while maintaining the same isolated packaging architecture.

Replacement Considerations

Direct replacements must match the 1800V/500A rating and isolated package dimensions. Verify pinout compatibility and thermal resistance specifications. Cross-reference with other POW-R-BLOK variants if exact ratings differ slightly, ensuring the substitute maintains the necessary electrical isolation and mechanical mounting interface.