1KSMB43C Equivalent & Substitute Parts

Part Overview

The 1KSMB43C is a transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for telecom applications. This bidirectional zener diode operates with a reverse standoff voltage of 36.8V and provides clamping protection at 59.3V with a peak pulse current rating of 16.9A. The device is packaged in a DO-214AA (SMB) surface mount configuration and rated for 1000W peak pulse power dissipation.

The 1KSMB43C carries an obsolete product status. Identifying equivalent substitute parts is necessary to ensure design continuity, maintain supply chain reliability, and support ongoing production or maintenance requirements for systems utilizing this component.

Substiute Parts

1KSMB43C

Littelfuse Inc.In Stock: 11331KSMB43C Datasheet

Current PartRFQ

1KSMB43CA

Taiwan Semiconductor CorporationIn Stock: 20281KSMB43CA Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1KSMB43C is determined by electrical and mechanical parameter equivalence. The following criteria establish valid substitution:

Electrical Parameters (Must Match):

• Voltage - Reverse Standoff (Typ): 36.8V
• Voltage - Breakdown (Min): 40.9V
• Voltage - Clamping (Max) @ Ipp: 59.3V
• Current - Peak Pulse (10/1000µs): 16.9A
• Power - Peak Pulse: 1000W
• Bidirectional Channels: 1
• Type: Zener

Mechanical Parameters (Must Match):

• Package / Case: DO-214AA, SMB
• Mounting Type: Surface Mount

The 1KSMB43CA, manufactured by Taiwan Semiconductor Corporation, satisfies all electrical and mechanical equivalence criteria. This part maintains identical voltage ratings, current handling, and power dissipation specifications while preserving the same surface mount package configuration.

Parameter Comparison

Engineering Selection Recommendations

The 1KSMB43CA is a direct electrical and mechanical equivalent to the 1KSMB43C. Selection of the 1KSMB43CA is supported by the following factors:

Product Status: The 1KSMB43CA maintains active product status, ensuring ongoing availability and supply chain support compared to the obsolete 1KSMB43C.

Compliance: Both parts are RoHS compliant. The 1KSMB43CA carries ROHS3 compliance certification, meeting current regulatory requirements. The 1KSMB43CA is also REACH unaffected, confirming compliance with chemical substance regulations.

Electrical Equivalence: All critical electrical parameters—reverse standoff voltage, breakdown voltage, clamping voltage, peak pulse current, and power dissipation—are identical between the two parts.

Thermal Performance: The 1KSMB43CA provides an extended operating temperature range (-55°C to 175°C) compared to the 1KSMB43C (-65°C to 150°C), offering improved thermal margin in applications operating at elevated temperatures.

Packaging: Both parts utilize identical DO-214AA (SMB) surface mount packaging, ensuring mechanical compatibility with existing PCB layouts and assembly processes.

Frequently Asked Questions (FAQ)

Q: Can the 1KSMB43CA be used as a direct replacement for the 1KSMB43C?

A: Yes. The 1KSMB43CA is electrically and mechanically equivalent to the 1KSMB43C. All voltage ratings, current specifications, power dissipation, and package configurations are identical. The part can be substituted without circuit modification.

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

A: The 1KSMB43C operates from -65°C to 150°C (TJ), while the 1KSMB43CA operates from -55°C to 175°C (TJ). The 1KSMB43CA provides a wider upper temperature limit, beneficial for high-temperature applications. The lower temperature limit of the 1KSMB43CA is -55°C compared to -65°C for the original part.

Q: Are there packaging differences between the 1KSMB43C and 1KSMB43CA?

A: Both parts use the DO-214AA (SMB) surface mount package. The 1KSMB43C is supplied in standard packaging, while the 1KSMB43CA is supplied in Tape & Reel (TR) format. This difference affects handling and assembly processes but does not impact electrical or mechanical compatibility.

Q: What compliance certifications apply to the 1KSMB43CA?

A: The 1KSMB43CA is ROHS3 compliant and REACH unaffected. Both parts carry EAR99 export classification and are assigned HTSUS code 8541.10.0080.

Q: Why is the 1KSMB43C listed as obsolete?

A: The 1KSMB43C has reached end-of-life status with Littelfuse Inc. The 1KSMB43CA, manufactured by Taiwan Semiconductor Corporation, provides functional continuity for applications requiring this voltage and current rating specification.

Q: Are there any electrical performance differences between the two parts?

A: No. Both parts are specified with identical electrical parameters: 36.8V reverse standoff voltage, 40.9V minimum breakdown voltage, 59.3V maximum clamping voltage, 16.9A peak pulse current, and 1000W peak pulse power dissipation.