LD420850

Overview

The Powerex LD420850 is a dual SCR/diode isolated module within the POW-R-BLOK series, rated for 800 Volts and 500 Amperes. It features an aluminum nitride isolator providing 3000 Vrms isolation at 25°C. The device supports a repetitive peak forward/reverse blocking voltage up to 1600V across the series. Electrical characteristics include a peak on-state voltage of 1.30V at 1500A and a maximum rate-of-rise of on-state current (di/dt) of 200 A/µs. Thermal resistance from junction to case is 0.0325°C/W per module. Operating temperature ranges from -40°C to +130°C.

Feature Summary

• Electrically isolated heatsinking via aluminum nitride substrate
• Compression bonded elements with metal baseplate
• Low thermal impedance for improved current capability
• UL recognized packaging

Applications

• Bridge circuits
• AC & DC motor drives
• Battery supplies
• Power supplies
• Large IGBT circuit front ends

Procurement Notes

Verify the specific voltage suffix in the part number against the required blocking voltage rating. Confirm mounting torque specifications for M6 and M10 screws match the assembly requirements. Ensure the datasheet revision date aligns with the manufacturing batch for accurate thermal coefficient data.

Selection Notes

Select based on the voltage code representing the blocking voltage in hundreds of volts. Verify the RMS forward current rating against the application's conduction angle and case temperature. Check di/dt ratings to ensure compatibility with the gate drive circuitry and snubber networks.

Part Context

This component belongs to the LD42__50 family of dual SCR/diode modules. The series offers various voltage ratings from 800V to 1600V while maintaining a consistent 500A current rating and physical outline dimensions.

Replacement Considerations

Cross-reference with other LD42__50 variants for different voltage ratings. Verify mechanical footprint compatibility with existing heatsink mounting holes.