Q4008LTHTP

Triacs Overview

The Littelfuse Q4008LTHTP is a Quadrac device, which integrates a triac and a diac trigger within a single package. It serves as a bidirectional AC switch with gate control for either polarity of main terminal voltage. The component features an on-state RMS current capacity of 8 A and a rated repetitive off-state voltage (VDRM) of 400 V. It operates within a temperature range of -40°C to +125°C and utilizes a TO-220 package. The device includes glass-passivated junctions for reliability and offers electrical isolation of 2500 V rms from leads to the mounting surface.

Triacs Feature Summary

• Integrated diac trigger eliminates the need for discrete components and assembly time
• Alternistor design removes the requirement for external snubber networks
• Electrically isolated package provides safety without separate insulators
• Glass-passivated junctions ensure long-term parameter stability

Triacs Applications

• AC speed controls
• Temperature modulation controls
• Lighting controls requiring noise immunity

Triacs Procurement Notes

Verify the specific suffix 'HT' against official Littelfuse documentation to confirm the alternistor variant characteristics. Ensure the ordering code matches the required thermal and electrical specifications for the target application before finalizing procurement.

Triacs Selection Notes

Select this component when phase control applications require high noise immunity and simplified circuit topology. The integrated design reduces board space and assembly complexity compared to discrete triac-diac combinations. Verify that the 400 V rating and 8 A current capacity align with the load requirements.

Triacs Part Context

This part belongs to the QxxxxLTH series of Teccor brand Quadrac devices developed by Littelfuse. These devices are designed to replace standard gated triacs paired with external diacs, offering a consolidated solution for AC switching applications in industrial and consumer electronics.

Triacs Replacement Considerations

Direct replacements must be verified against the QxxxxLTH series datasheet. Substitutes should match the 8 A current rating, 400 V blocking voltage, and TO-220 package form factor while maintaining the integrated diac functionality.