SMAJ43 Equivalent & Substitute Parts Reference

Part Overview

The SMAJ43 is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for telecom applications. This component features a 43V reverse standoff voltage with a 69.4V maximum clamping voltage and 5.8A peak pulse current capability in a surface mount DO-214AC (SMA) package. The SMAJ43 is classified as obsolete, necessitating identification of active equivalent parts to maintain design continuity and ensure supply chain availability for new production and maintenance applications.

Substiute Parts

SMAJ43

Littelfuse Inc.In Stock: 5861SMAJ43 Datasheet

Current PartRFQ

SMAJ43A

MDDIn Stock: 18896SMAJ43A Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMAJ43 is determined by strict electrical and mechanical parameter matching within the Transient Voltage Suppressor category. The following parameters establish substitution eligibility:

Critical Electrical Parameters:

• Voltage - Reverse Standoff (Typ): 43V
• Voltage - Breakdown (Min): 47.8V
• Voltage - Clamping (Max) @ Ipp: 69.4V
• Current - Peak Pulse (10/1000µs): 5.8A
• Power - Peak Pulse: 400W

Critical Mechanical Parameters:

• Package / Case: DO-214AC, SMA
• Mounting Type: Surface Mount
• Unidirectional Channels: 1
• Type: Zener

The SMAJ43A qualifies as a direct substitute because it maintains identical electrical specifications across all voltage and current ratings, identical package configuration, and identical mounting methodology. Both components are classified as unidirectional Zener-type TVS diodes with single-channel architecture.

Parameter Comparison

Engineering Selection Recommendations

The SMAJ43A manufactured by MDD is a direct electrical and mechanical equivalent to the obsolete SMAJ43. Selection of the SMAJ43A is supported by the following factors:

Electrical Compatibility: All voltage specifications (reverse standoff, breakdown, and clamping) and current ratings are identical, ensuring functional equivalence in circuit protection applications.

Mechanical Compatibility: Both components utilize the DO-214AC (SMA) surface mount package with identical pinout and footprint, permitting direct board-level substitution without layout modification.

Compliance Status: The SMAJ43A maintains RoHS3 compliance, meeting current environmental and regulatory requirements. Both components carry identical ECCN and HTSUS classifications.

Product Status Advantage: The SMAJ43A is classified as active, ensuring continued availability and supply chain support, whereas the SMAJ43 is obsolete.

Operating Temperature Consideration: The SMAJ43A operates across a narrower temperature range (-50°C to 150°C) compared to the SMAJ43 (-65°C to 150°C). Applications requiring operation below -50°C require evaluation against specific design requirements.

Frequently Asked Questions (FAQ)

Q: Can the SMAJ43A be used as a direct replacement for the SMAJ43 in existing designs?

A: Yes. The SMAJ43A provides identical electrical performance across all voltage and current parameters and shares the same DO-214AC (SMA) package footprint. Direct substitution is supported for applications operating within the -50°C to 150°C temperature range.

Q: What is the primary difference between the SMAJ43 and SMAJ43A?

A: The primary difference is product status and operating temperature range. The SMAJ43 is obsolete with an operating range of -65°C to 150°C, while the SMAJ43A is active with an operating range of -50°C to 150°C. All electrical specifications are identical.

Q: Are there packaging differences between these parts?

A: No. Both the SMAJ43 and SMAJ43A use the DO-214AC (SMA) surface mount package. The SMAJ43A is available in Tape & Reel (TR) packaging format, which is standard for active production components.

Q: Does the SMAJ43A meet current RoHS requirements?

A: Yes. The SMAJ43A is ROHS3 compliant, meeting current environmental and regulatory standards for electronic components.

Q: What applications are supported by the SMAJ43A?

A: The SMAJ43A is classified for general purpose applications. The original SMAJ43 was specified for telecom applications. The SMAJ43A electrical specifications support both telecom and general purpose transient voltage suppression requirements.

Q: Is the SMAJ43A suitable for low-temperature applications below -50°C?

A: The SMAJ43A is rated for operation down to -50°C. Applications requiring operation below -50°C must be evaluated against specific design requirements and alternative components with extended low-temperature ratings.