Q4008RH3

Triacs Overview

The Littelfuse Q4008RH3 is a high-reliability Alternistor TRIAC designed for robust power control applications. It features an 8 A RMS on-state current and a 400 V rated repetitive off-state voltage, housed in a TO-220-3 through-hole package. The device operates within a temperature range of -40 °C to +125 °C. Key electrical characteristics include a maximum holding current of 35 mA, a gate trigger voltage of 1.3 V, and a gate trigger current of 35 mA. It exhibits a low on-state voltage of 1.6 V and a leakage current of 10 uA at the rated voltage.

Triacs Feature Summary

• High reliability construction suitable for demanding industrial environments
• Alternistor technology providing enhanced commutation performance
• Robust thermal management via TO-220-3 through-hole mounting

Triacs Applications

• Industrial motor speed control systems
• Solid state relays requiring high commutation capability
• Power regulation circuits in harsh operating conditions

Triacs Procurement Notes

Verify the specific suffix RH3 against official Littelfuse documentation to confirm pinout and exact electrical tolerances. Ensure the procurement channel provides valid RoHS compliance certificates and original manufacturer traceability. Cross-reference the datasheet revision date to guarantee alignment with current manufacturing standards before finalizing orders.

Triacs Selection Notes

Select this component when high dv/dt immunity and reliable commutation are critical requirements. The TO-220-3 package facilitates effective heat dissipation for continuous 8 A loads. Compare the 35 mA gate trigger threshold against available drive circuit capabilities to ensure sufficient triggering margin under varying temperature conditions.

Triacs Part Context

This part belongs to the Qxx08xHx series of Alternistor TRIACs from Littelfuse. These devices utilize specialized silicon structures to improve switching performance compared to standard triacs. The series is engineered for applications where rapid load changes or inductive loads challenge conventional thyristor operation.

Triacs Replacement Considerations

Direct replacements must match the 8 A / 400 V rating and TO-220-3 footprint. Verify that substitute parts offer equivalent or superior dv/dt ratings and hold-off currents. Confirm that the alternative device's gate sensitivity aligns with existing driver circuitry constraints.