Q4X8E3

Triacs Overview

The Littelfuse Q4X8E3 is a bidirectional triac in the QxX8Ex series, housed in a TO-92-3 through-hole package. It supports an RMS current (It RMS) of 800 mA with non-repetitive surge currents of 8.3 A and 10 A. The device features a rated repetitive off-state voltage (VDRM) of 400 V and a maximum holding current (Ih) of 15 mA. Gate triggering parameters include a voltage (Vgt) of 2 V and currents of 10 mA or 25 mA. On-state voltage is 1.6 V, with leakage current at 20 uA under VDRM conditions. Operating temperatures range from -65 C to +125 C.

Triacs Feature Summary

• Sensitive gate type designed for reliable control in quadrants I and IV, facilitating integration with digital control circuitry.
• Glass-passivated junctions provide protection against environmental factors and enhance component longevity.
• Solid-state switching architecture eliminates mechanical contact bounce and arcing, reducing electromagnetic interference generation.

Triacs Applications

• AC solid-state switches
• Lighting controls and light dimmers
• Motor speed modulation controls

Triacs Procurement Notes

Verify the specific Littelfuse datasheet for the Q4X8E3 to confirm RoHS compliance status and REACH SVHC details before finalizing procurement. Ensure the ordering suffix matches the required bulk packaging quantity of 2000 units. Cross-reference the manufacturer's official documentation to validate the exact pinout configuration for MT1, MT2, and Gate terminals within the TO-92-3 package.

Triacs Selection Notes

Select this component when a sensitive gate triac is required for quadrant I and IV operation in digital control systems. The 400 V rating suits low-voltage AC applications, while the 800 mA RMS current defines its load capacity. Verify that the 15 mA holding current aligns with the minimum load requirements of the target circuit to prevent unintended turn-off during operation.

Triacs Part Context

The Q4X8E3 belongs to the Lxx08xx & Qxx08xx & Qxx08xHx series of high commutation triacs manufactured by Littelfuse. This family is engineered for AC switching and phase control tasks. The 'Q' designation typically indicates a sensitive gate variant optimized for compatibility with modern digital logic interfaces compared to standard gate alternatives.

Triacs Replacement Considerations

Consult the official Littelfuse selection guide for direct replacements within the QxX8Ex series. Verify that any substitute part maintains the same 400 V rating, 800 mA current capacity, and sensitive gate characteristics to ensure functional equivalence in existing designs.

Triacs FAQ

What are the operating quadrants for the Q4X8E3?

As a sensitive type triac, the Q4X8E3 guarantees gate control in quadrants I and IV, making it suitable for digital control circuitry applications.

What is the isolation rating of the Q4X8E3 package?

The documentation specifies a 2500 Vrms isolation rating for the L-package used in this series, though users should verify this specific parameter in the Q4X8E3 datasheet.

How does the Q4X8E3 handle transient events?

The device utilizes glass-passivated junctions and solid-state switching to eliminate arcing and contact bounce, which helps restrict RFI generation during activation.