Equivalent & Substitute Parts for L4X8E3 TRIAC Sensitive Gate Thyristor

Part Overview

The L4X8E3 is a Logic-Sensitive Gate TRIAC manufactured by Littelfuse Inc., rated for 400V off-state voltage with 800mA on-state current in a TO-92 through-hole package. This component is actively produced and widely used in AC switching applications requiring low gate trigger voltage. Substitute parts are identified when equivalent functional performance can be maintained within the allowed electrical and mechanical parameter ranges for TRIAC thyristors in this category.

Substiute Parts

L4X8E3

Littelfuse Inc.In Stock: 2401L4X8E3 Datasheet

Current PartRFQ

Z0103MA 1AA2

STMicroelectronicsIn Stock: 90422Z0103MA 1AA2 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the L4X8E3 TRIAC is determined by the following critical parameters:

• Triac Type Classification: Must be Logic-Sensitive Gate configuration
• Voltage Rating: Off-state voltage must be equal to or greater than 400V
• Current Rating: On-state current (It RMS) must be equal to or greater than 800mA
• Gate Trigger Characteristics: Vgt and Igt must remain within acceptable limits for sensitive-gate operation
• Package Compatibility: Must use TO-92 or equivalent through-hole package
• Thermal Range: Operating temperature range must accommodate the application environment
• Compliance: RoHS3 compliance and MSL rating must be maintained

The substitute part Z0103MA 1AA2 from STMicroelectronics meets these criteria with higher voltage and current ratings, maintaining the same gate trigger voltage specification and package form factor.

Parameter Comparison

Engineering Selection Recommendations

The Z0103MA 1AA2 serves as a direct substitute for the L4X8E3 based on the following engineering criteria:

• Both components maintain ROHS3 compliance and identical MSL ratings, ensuring regulatory and environmental compatibility
• Both are actively produced, providing supply chain continuity
• The substitute's higher voltage (600V) and current (1A) ratings provide design margin for 400V/800mA applications
• Gate trigger specifications are identical, ensuring control circuit compatibility without modification
• Through-hole TO-92 package compatibility allows direct board-level substitution
• The substitute's extended upper operating temperature range (-40°C to 125°C) accommodates higher-temperature environments, though applications requiring temperatures below -40°C should verify thermal performance requirements

Frequently Asked Questions (FAQ)

Q: Can the Z0103MA 1AA2 be used as a direct replacement for the L4X8E3 in existing designs?

A: Yes. Both components share identical gate trigger voltage (1.3V max) and current (3mA max) specifications, identical package form factor (TO-92-3), and identical RoHS3 compliance. The substitute's higher voltage and current ratings provide additional design margin without requiring circuit modification.

Q: What is the primary difference between these two TRIACs?

A: The Z0103MA 1AA2 has higher voltage (600V vs. 400V) and current (1A vs. 800mA) ratings. Both maintain the same sensitive-gate trigger characteristics and package configuration.

Q: Are there any thermal considerations when substituting?

A: The L4X8E3 operates from -65°C to 110°C, while the Z0103MA 1AA2 operates from -40°C to 125°C. Applications requiring operation below -40°C should retain the L4X8E3. Applications in higher-temperature environments may benefit from the substitute's extended upper range.

Q: Do both parts have the same moisture sensitivity level?

A: Yes. Both components are rated MSL 1 (Unlimited), indicating no moisture sensitivity restrictions for storage or handling.

Q: Is the package footprint identical between these parts?

A: Yes. Both use the TO-226-3 / TO-92-3 package, allowing direct board-level substitution without layout changes.