SMCJ43 Equivalent & Substitute Parts

Part Overview

The SMCJ43 is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for transient overvoltage protection in telecom applications. This component features a 43V reverse standoff voltage with a 69.4V maximum clamping voltage and 21.7A peak pulse current capability in a surface mount DO-214AB (SMC) package.

The SMCJ43 carries an Obsolete product status. Identifying equivalent substitute parts ensures design continuity and supply chain reliability for applications requiring this voltage suppression specification.

Substiute Parts

SMCJ43

Littelfuse Inc.In Stock: 933SMCJ43 Datasheet

Current PartRFQ

SMCJ43A

MDDIn Stock: 1428SMCJ43A Datasheet

DirectRFQ

SMCJ43A

MDDIn Stock: 1428SMCJ43A Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SMCJ43 are identified based on electrical and mechanical parameter equivalence. The following criteria determine substitution validity:

Electrical Parameters (Critical):

• Voltage - Reverse Standoff (Typ): 43V
• Voltage - Breakdown (Min): 47.8V
• Voltage - Clamping (Max) @ Ipp: 69.4V
• Current - Peak Pulse (10/1000µs): 21.7A
• Power - Peak Pulse: 1500W

Mechanical Parameters (Critical):

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

Functional Parameters:

• Category: Transient Voltage Suppressors (TVS)

The SMCJ43A meets all electrical and mechanical equivalence criteria and is classified as a direct substitute.

Parameter Comparison

Engineering Selection Recommendations

The SMCJ43A (MDD) is a direct electrical and mechanical equivalent to the obsolete SMCJ43 (Littelfuse Inc.). All critical voltage, current, and power specifications are identical. Both components utilize the same DO-214AB (SMC) surface mount package and share identical moisture sensitivity ratings.

Product Status Consideration: The SMCJ43A carries Active product status, ensuring ongoing availability and supply chain support compared to the Obsolete SMCJ43.

Compliance Status: Both parts are RoHS compliant. The SMCJ43A meets ROHS3 compliance and is REACH Unaffected, providing enhanced regulatory alignment for current manufacturing standards.

Operating Temperature: The SMCJ43A operates across -50°C to 150°C, compared to the SMCJ43 range of -65°C to 150°C. Applications requiring operation below -50°C require evaluation against specific design requirements.

Inventory Availability: The SMCJ43A demonstrates higher current inventory levels (1330 Pcs) relative to the SMCJ43 (883 Pcs), supporting procurement reliability.

Frequently Asked Questions (FAQ)

Q: Can the SMCJ43A directly replace the SMCJ43 in existing designs?

A: Yes. The SMCJ43A meets all electrical specifications (voltage, current, power) and mechanical requirements (package, mounting type) of the SMCJ43. Both components are unidirectional Zener TVS diodes in DO-214AB surface mount packages with identical suppression characteristics.

Q: What is the difference in operating temperature range between these parts?

A: The SMCJ43 operates from -65°C to 150°C, while the SMCJ43A operates from -50°C to 150°C. The SMCJ43A has a narrower lower temperature limit. Applications requiring operation below -50°C must confirm compatibility with design specifications.

Q: Are there package compatibility concerns?

A: No. Both the SMCJ43 and SMCJ43A use the DO-214AB (SMC) surface mount package. PCB footprints and assembly processes are identical.

Q: Why is the SMCJ43 listed as Obsolete?

A: The SMCJ43 carries Obsolete product status from Littelfuse Inc. The SMCJ43A (MDD) is an Active equivalent that provides continued availability for this voltage suppression specification.

Q: Do both parts meet current RoHS requirements?

A: Yes. The SMCJ43 is RoHS Compliant, and the SMCJ43A is ROHS3 Compliant. Both meet current environmental and regulatory standards. The SMCJ43A additionally carries REACH Unaffected status.

Q: What are the key electrical parameters that define substitution?

A: Substitution is determined by matching: Voltage - Reverse Standoff (43V), Voltage - Breakdown (47.8V), Voltage - Clamping (69.4V), Current - Peak Pulse (21.7A), and Power - Peak Pulse (1500W). The SMCJ43A matches all these specifications.