Q4008RH4TP

Triacs Overview

The Littelfuse Q4008RH4TP 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 junction temperature range of -40°C to +125°C and utilizes a TO-220AC package with through-hole mounting. Key electrical parameters include a maximum holding current of 35 mA, a gate trigger voltage of 1.3 V, and a gate trigger current of 35 mA. The non-repetitive peak on-state current ratings are specified at 83 A and 100 A, while the on-state voltage is 1.6 V.

Triacs Feature Summary

• Alternistor technology provides high commutation capability suitable for circuits requiring high dv/dt performance.
• Operates in Quadrants I, II, and III, enabling reliable triggering from the AC line without requiring digital control circuitry.
• Designed for robust AC switching and phase control in motor speed modulation and lighting applications.

Triacs Applications

• Motor speed controls
• Temperature modulation systems
• Lighting controls
• Static switching relays

Triacs Procurement Notes

Verify the specific suffix against official Littelfuse documentation to confirm pinout and thermal characteristics. Ensure the procurement channel sources directly from authorized distributors to guarantee component authenticity. 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 for AC line triggering without sensitive gate drivers. Compare the 35 mA gate trigger current against standard triacs if digital interface compatibility is not a priority. Verify that the 400 V voltage rating aligns with the peak line voltage and transient requirements of the target AC circuit design.

Triacs Part Context

This part belongs to the Qxx08xHx series of 8 Amp bi-directional solid state switches. It complements the standard Q4008L4TP by offering enhanced commutation capabilities through its Alternistor architecture. The series is engineered for general-purpose AC power control where reliability under rapid voltage changes is critical.

Triacs Replacement Considerations

Direct substitutes within the same family include the Q4008RH467TP. Verify pin compatibility and thermal resistance values before swapping with other 8A triacs such as the Q4008N4TP56 or Q4008L4TP, as gate sensitivity and quadrant operation differ significantly between Standard and Alternistor types.