Q4008L5

Triacs Overview

The Littelfuse Q4008L5 is a standard triac designed for AC power control applications. It features an 8 A RMS on-state current and a 400 V rated repetitive off-state voltage. The device operates within a junction temperature range of -40°C to +125°C. Key electrical parameters include a maximum holding current of 50 mA, a gate trigger voltage of 2.5 V, and a gate trigger current of 50 mA. It exhibits a typical on-state voltage of 1.6 V and a maximum off-state leakage current of 50 µA at the rated voltage.

Triacs Feature Summary

• Provides bidirectional AC switching capability with high thermal stability
• Features sensitive gate triggering for direct microprocessor interface compatibility
• Utilizes isolated tab construction for simplified mounting and heat dissipation

Triacs Applications

• Solid-state relays
• Motor speed controls
• Lighting dimmers

Triacs Procurement Notes

Verify the specific datasheet revision and RoHS compliance status directly with Littelfuse or authorized distributors before procurement. Confirm that the TO-220 package variant matches the required isolation specifications for the target circuit design. Ensure gate trigger requirements align with the driving logic levels available in the application system.

Triacs Selection Notes

Select this component when an 8 A current rating and 400 V blocking voltage are sufficient for the load. The TO-220 package requires appropriate heatsinking for continuous operation near the 8 A limit. Verify that the 50 mA holding current does not cause unintended turn-off in low-load scenarios compared to lower-holding-current alternatives.

Triacs Part Context

This part belongs to the Littelfuse Q series of standard triacs, which are widely used in general-purpose AC power switching. The Q4008L5 specifically targets applications requiring moderate current handling with reliable gate sensitivity. It serves as a robust alternative to silicon-controlled rectifiers (SCRs) where bidirectional conduction is necessary.

Triacs Replacement Considerations

Equivalent parts include the Q4008L4TP and Q4008DH4RP from Littelfuse, provided the packaging and specific gate current ratings match the board layout and drive circuit constraints.