SMLJ40A-Q Equivalent & Substitute Parts

Part Overview

The SMLJ40A-Q is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Bourns Inc., designed for surface mount applications in the DO-214AB (SMC) package. This component provides transient overvoltage protection with a 40V reverse standoff voltage and 64.5V maximum clamping voltage. The part is actively produced, AEC-Q101 qualified for automotive applications, and RoHS3 compliant. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are required due to inventory availability, supply chain considerations, or design flexibility.

Substiute Parts

SMLJ40A-Q

Bourns Inc.In Stock: 908SMLJ40A-Q Datasheet

Current PartRFQ

SMDJE40AH

Eaton - Electronics DivisionIn Stock: 3609SMDJE40AH Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMLJ40A-Q is determined by strict equivalence across the following critical parameters:

• Voltage - Reverse Standoff: 40V (nominal)
• Voltage - Breakdown (Min): 44.4V
• Voltage - Clamping (Max) @ Ipp: 64.5V
• Current - Peak Pulse (10/1000µs): ≥46.4A
• Power - Peak Pulse: 3000W
• Package / Case: DO-214AB, SMC (surface mount)
• Unidirectional Channels: 1
• Operating Temperature Range: -55°C to 150°C (TJ)
• Automotive Grade and AEC-Q101 Qualification

The SMDJE40AH from Eaton - Electronics Division meets all substitution criteria with equivalent electrical ratings and identical package specifications.

Parameter Comparison

Engineering Selection Recommendations

The SMDJE40AH is a direct equivalent substitute for the SMLJ40A-Q. Both components are active products with identical automotive-grade specifications and AEC-Q101 qualification. Both maintain RoHS3 compliance and identical regulatory classifications (ECCN: EAR99, HTSUS: 8541.10.0080). The peak pulse current specification of the SMDJE40AH (46.5A) exceeds the minimum requirement of 46.4A, ensuring functional compatibility. Surface mount package compatibility (DO-214AB, SMC) and operating temperature range (-55°C to 150°C) are identical. Selection between these parts may be based on inventory availability, lead time, or supply chain preference without compromising circuit performance or compliance requirements.

Frequently Asked Questions (FAQ)

Q: Can the SMDJE40AH replace the SMLJ40A-Q in existing designs?

A: Yes. The SMDJE40AH meets all electrical and mechanical specifications required for direct substitution. Both parts share identical voltage ratings (40V standoff, 64.5V clamping), current handling (46.4A minimum), power dissipation (3000W), package type (DO-214AB, SMC), and automotive qualifications (AEC-Q101).

Q: Are there any compliance or certification differences between these parts?

A: No. Both the SMLJ40A-Q and SMDJE40AH are AEC-Q101 qualified, RoHS3 compliant, and classified under the same regulatory codes (ECCN: EAR99, HTSUS: 8541.10.0080). Moisture sensitivity levels are identical (MSL 1, Unlimited).

Q: What is the significance of the peak pulse current difference (46.4A vs. 46.5A)?

A: The SMDJE40AH specification of 46.5A exceeds the SMLJ40A-Q requirement of 46.4A. This represents a 0.2% margin and confirms functional equivalence. Both parts meet or exceed the circuit protection requirements.

Q: Are the packages physically identical?

A: Yes. Both parts use the DO-214AB (SMC) surface mount package. PCB footprints, solder pad layouts, and mounting procedures are identical. No design modifications are required for substitution.

Q: What operating temperature range applies to both parts?

A: Both the SMLJ40A-Q and SMDJE40AH operate across -55°C to 150°C (junction temperature). This range is identical and suitable for automotive applications.

Q: Can these parts be used interchangeably in high-reliability applications?

A: Yes. Both parts carry automotive-grade designation and AEC-Q101 qualification, meeting high-reliability standards. Electrical performance, thermal characteristics, and compliance certifications are equivalent.