1KSMB43 Equivalent & Substitute Parts

Part Overview

The 1KSMB43 is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose transient voltage protection in surface-mount applications. This component features a 36.8V reverse standoff voltage with a 62.27V maximum clamping voltage and 16.9A peak pulse current capability in a DO-214AA (SMB) package. The part is currently listed as obsolete, necessitating identification of active equivalent alternatives that maintain electrical and mechanical compatibility for ongoing production and repair applications.

Substiute Parts

1KSMB43

Littelfuse Inc.In Stock: 9401KSMB43 Datasheet

Current PartRFQ

1KSMB43A

Taiwan Semiconductor CorporationIn Stock: 421771KSMB43A Datasheet

DirectRFQ

P6SMB43A

Eaton - Electronics DivisionIn Stock: 148264P6SMB43A Datasheet

MFR RecommendedRFQ

SMBJP6KE43A-TP

Micro Commercial CoIn Stock: 1107SMBJP6KE43A-TP Datasheet

MFR RecommendedRFQ

TVP06B430A-G

Comchip TechnologyIn Stock: 1070TVP06B430A-G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 1KSMB43 are qualified based on the following critical parameters that determine functional equivalence:

• Voltage - Reverse Standoff (Typ): 36.8V
• Package / Case: DO-214AA, SMB (surface-mount compatibility)
• Mounting Type: Surface Mount
• Type: Zener, Unidirectional
• Unidirectional Channels: 1

The substitute parts listed maintain the same reverse standoff voltage and package form factor, ensuring direct mechanical and electrical compatibility. Variations in clamping voltage and peak pulse current are documented in the parameter comparison table below.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: 1KSMB43A (Taiwan Semiconductor Corporation)

The 1KSMB43A is the closest electrical equivalent, maintaining identical reverse standoff voltage (36.8V), peak pulse current (16.9A), and peak pulse power (1000W). This part is in active production status with ROHS3 compliance and offers an extended operating temperature range (-55°C ~ 175°C). This part is recommended for applications requiring full parameter matching with the original 1KSMB43.

Secondary Substitutes: P6SMB43A (Eaton) and SMBJP6KE43A-TP (Micro Commercial)

Both P6SMB43A and SMBJP6KE43A-TP maintain the critical 36.8V reverse standoff voltage and DO-214AA SMB package compatibility. However, these parts operate at reduced peak pulse current (10.3A) and peak pulse power (600W) compared to the original specification. These substitutes are suitable for applications where the full 16.9A peak pulse current is not required. Both parts are in active production with appropriate compliance certifications.

TVP06B430A-G (Comchip Technology)

The TVP06B430A-G is qualified as a substitute based on package compatibility and active product status. However, critical electrical parameters including reverse standoff voltage, breakdown voltage, clamping voltage, and peak pulse current are not specified in available documentation. This part should be selected only when complete parameter data can be independently verified.

Frequently Asked Questions (FAQ)

Q: Can the 1KSMB43A directly replace the obsolete 1KSMB43?

A: Yes. The 1KSMB43A maintains identical reverse standoff voltage (36.8V), peak pulse current (16.9A), and peak pulse power (1000W). Both use the DO-214AA SMB package. The 1KSMB43A is in active production status and offers an extended operating temperature range.

Q: What is the difference between the 1KSMB43A and P6SMB43A?

A: Both parts share the same 36.8V reverse standoff voltage and DO-214AA SMB package. The primary difference is peak pulse current: the 1KSMB43A supports 16.9A while the P6SMB43A supports 10.3A. Peak pulse power differs accordingly (1000W vs 600W). Select based on your circuit's transient current requirements.

Q: Are all substitute parts RoHS compliant?

A: Yes. All listed substitute parts carry RoHS compliance certifications (ROHS3 or RoHS Compliant). All parts have Moisture Sensitivity Level 1 (Unlimited), indicating no special moisture handling requirements.

Q: Can I use P6SMB43A in a design originally specified for 1KSMB43?

A: The P6SMB43A is mechanically and electrically compatible for the voltage protection function. However, it is rated for 10.3A peak pulse current versus the original 16.9A specification. Use this part only if your circuit's transient current does not exceed 10.3A.

Q: What package options are available for these TVS diodes?

A: All listed parts use the DO-214AA (SMB) surface-mount package. This is a standard package for transient voltage suppression diodes and ensures compatibility with existing PCB layouts designed for the 1KSMB43.

Q: Which substitute offers the widest operating temperature range?

A: Both the 1KSMB43A and SMBJP6KE43A-TP support -55°C ~ 175°C operating temperature range, which is 25°C wider than the original 1KSMB43 specification of -55°C ~ 150°C.