Q401E4

Triacs Overview

The Littelfuse Q401E4 is a bidirectional triac from the Qx01E series, designed for AC switching and phase control applications. It features a 400 V rated repetitive off-state voltage (VDRM) and supports an RMS on-state current of 1 A. The device operates within a temperature range of -65 °C to +125 °C and utilizes a TO-92 through-hole package. Key electrical characteristics include a maximum holding current of 15 mA, a gate trigger voltage of 2.5 V, and a gate trigger current ranging from 25 mA to 50 mA. Non-repetitive peak currents are specified at 16.7 A and 20 A, with an on-state voltage of 1.6 V and a leakage current of 5 µA under rated conditions.

Triacs Feature Summary

• Bidirectional AC switching capability for phase control circuits
• Glass-passivated junctions for parameter stability and reliability
• Through-hole TO-92 packaging for standard board mounting

Triacs Applications

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

Triacs Procurement Notes

Verify component authenticity by cross-referencing the manufacturer part number Q401E4 with official Littelfuse documentation. Confirm RoHS compliance status and specific lot traceability requirements against the latest datasheet before procurement. Ensure storage conditions align with semiconductor handling standards to maintain device integrity upon receipt.

Triacs Selection Notes

Select this component when a 400 V blocking voltage and 1 A continuous current rating are required for low-power AC load control. The TO-92 package is suitable for prototyping or low-volume assemblies where through-hole mounting is preferred. Verify that the gate trigger current specifications match the driving circuit capabilities to ensure reliable turn-on across the full operating temperature range.

Triacs Part Context

The Q401E4 belongs to the Qx01E series of Triacs manufactured by Littelfuse. This series is engineered for general-purpose AC power control applications. The device integrates glass-passivated junction technology to ensure long-term reliability and stable electrical parameters in commercial and industrial environments.

Triacs Replacement Considerations

Consult official Littelfuse substitution guides for verified equivalents. Cross-reference voltage ratings, current capacities, and package dimensions to ensure compatibility without modifying the existing circuit layout or thermal management design.

Triacs FAQ

What is the maximum non-repetitive peak on-state current for the Q401E4?

The non-repetitive on-state current is specified as 16.7 A and 20 A depending on the test condition.

Does the Q401E4 require an external snubber network?

The provided documentation does not explicitly state that an external snubber is unnecessary for this specific part number; however, Quadrac devices in related series often eliminate this need. Verify with the specific datasheet.

What is the operating temperature range for this triac?

The device is rated for operation between -65 °C and +125 °C.