T4050-6PF

Overview

The T4050-6PF is a Snubberless™ Triac in a TO-3PF through-hole package, rated for 40 A RMS on-state current and 600 V repetitive peak off-state voltage. It supports non-repetitive surge currents of up to 420 A (16.7 ms) or 400 A (20 ms). The device features high static and dynamic commutation with a minimum dV/dt immunity of 1000 V/µs and a critical rate of rise of on-state current ((dI/dt)c) of 25.1 A/ms at 125 °C. Maximum gate trigger current is 50 mA, and it operates within a junction temperature range of -40 °C to +125 °C.

Feature Summary

• Snubberless design eliminates the need for external RC snubber circuits
• High surge current capability for robust industrial performance
• UL1557 certified insulation with 2.5 kV isolation rating
• ECOPACK®2 compliant for RoHS and halogen-free requirements

Applications

• Heater, ventilation and air conditioning (HVAC)
• Solid state relay (SSR)
• Motor soft starter
• SMPS inrush current limiter

Procurement Notes

Verify the specific ordering code T4050-6PF against the manufacturer's official documentation to ensure correct voltage and current ratings. Confirm that the TO-3PF package dimensions and mounting torque specifications align with the target assembly requirements. Check for any recent datasheet revisions that may impact electrical characteristics or thermal resistance values before finalizing component selection.

Selection Notes

Select this component for applications requiring high surge tolerance and phase angle control without external snubbers. Ensure the thermal management design accounts for the junction-to-case thermal resistance of 1.45 °C/W maximum. Verify that the load current does not exceed the 40 A RMS limit at the expected case temperature of 76 °C. Consider the 50 mA maximum gate trigger current when designing the drive circuitry.

Part Context

This part belongs to STMicroelectronics' Snubberless™ Triac family, optimized for industrial applications demanding high immunity and surge current handling. It complements other logic-level and standard triacs by offering higher current capacity in a fully insulated plastic package. The series is designed to simplify system development by reducing external component count while maintaining high reliability in harsh environments.

Replacement Considerations

Direct replacements must match the 40 A RMS, 600 V rating and TO-3PF package. Verify equivalent Snubberless™ technology and commutation capabilities. Cross-reference UL certification file numbers if insulation compliance is required. Ensure thermal resistance and gate trigger parameters are compatible with existing drive circuits.

FAQ

What is the maximum non-repetitive surge current for the T4050-6PF?

The device supports a non-repetitive surge peak on-state current of 420 A for a 16.7 ms pulse and 400 A for a 20 ms pulse, with an initial junction temperature of 25 °C.

How is the insulation rating defined for this component?

The T4050-6PF is UL1557 certified (file ref. E81734) with an insulation RMS voltage rating of 2.5 kV measured for 1 minute.

What is the minimum dV/dt immunity at elevated temperatures?

At a junction temperature of 125 °C, the minimum static dV/dt immunity is specified as 1000 V/µs with the gate open and VD = 402 V.