Q4008LH4TP

Triacs Overview

The Littelfuse Q4008LH4TP is an Alternistor-type triac designed for AC switching and phase control applications. It features a rated repetitive off-state voltage (VDRM) of 400 V and an on-state RMS current (IT(RMS)) of 8 A. The device operates within a temperature range of -40°C to +125°C and utilizes a TO-220-2 through-hole package. Key electrical parameters include a maximum holding current of 50 mA, a gate trigger voltage of 2.5 V, and a gate trigger current ranging from 25 mA to 50 mA. It exhibits an on-state voltage of 1.6 V and a leakage current of 50 µA at VDRM.

Triacs Feature Summary

• Alternistor architecture provides high commutation capability without requiring external snubber networks.
• Sensitive gate design ensures reliable triggering in Quadrants I and IV for digital control compatibility.
• Glass-passivated junctions enhance long-term parameter stability and device reliability.

Triacs Applications

• Motor speed modulation controls
• Temperature modulation systems
• Lighting control circuits

Triacs Procurement Notes

Verify the specific suffix against official Littelfuse documentation to confirm pinout and isolation ratings. Ensure the procurement channel sources directly from authorized distributors to guarantee component authenticity and traceability. Cross-reference the datasheet revision date with manufacturing lot codes to validate compliance with current RoHS standards.

Triacs Selection Notes

Select this component when high dv/dt immunity is required in AC phase control circuits. The Alternistor type eliminates the need for complex snubber networks compared to standard triacs. Verify that the 400 V rating meets the peak line voltage requirements and that the 8 A RMS current capacity aligns with the load specifications.

Triacs Part Context

This part belongs to the Teccor Qxx08xx series of 8 Amp bi-directional solid state switches. The series includes sensitive, standard, and Alternistor variants. The Q4008LH4TP specifically denotes the Alternistor version within this family, optimized for high commutation performance in AC switching applications.

Triacs Replacement Considerations

Direct substitutes within the same series include Q4008L4TP for standard triac functionality. For higher voltage ratings, consider parts from the Q4008N4TP series. Verify pin compatibility and thermal characteristics before substituting with generic 8A triacs.