1KSMB10 Equivalent & Substitute Parts

Part Overview

The 1KSMB10 is a unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection in surface-mount applications. The device features an 8.55V reverse standoff voltage, 15.23V maximum clamping voltage, and 69A peak pulse current capability in a DO-214AA (SMB) package. The 1KSMB10 is classified as obsolete, necessitating identification of active equivalent and substitute parts that maintain functional compatibility within specified electrical and mechanical parameters.

Substiute Parts

1KSMB10

Littelfuse Inc.In Stock: 6981KSMB10 Datasheet

Current PartRFQ

1KSMB10A

Taiwan Semiconductor CorporationIn Stock: 92951KSMB10A Datasheet

DirectRFQ

SM6T10A-E3/52

Vishay General Semiconductor - Diodes DivisionIn Stock: 21823SM6T10A-E3/52 Datasheet

MFR RecommendedRFQ

SMBJ8.5A

Taiwan Semiconductor CorporationIn Stock: 44396SMBJ8.5A Datasheet

MFR RecommendedRFQ

SMBJ8.5A-E3/5B

Vishay General Semiconductor - Diodes DivisionIn Stock: 946SMBJ8.5A-E3/5B Datasheet

MFR RecommendedRFQ

SMBJ8V5A

Fairchild SemiconductorIn Stock: 35175SMBJ8V5A Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1KSMB10 is determined by the following critical parameters:

Electrical Compatibility Criteria:

• Voltage - Reverse Standoff (Typ): 8.5V to 8.55V
• Voltage - Clamping (Max) @ Ipp: 14.4V to 15.23V
• Current - Peak Pulse (10/1000µs): Minimum 41A (acceptable for reduced pulse current applications)
• Power - Peak Pulse: Minimum 600W

Mechanical Compatibility Criteria:

• Package / Case: DO-214AA, SMB (surface mount)
• Mounting Type: Surface Mount
• Unidirectional Channels: 1

Compliance Criteria:

• RoHS Status: ROHS3 Compliant
• Product Status: Active (preferred for new designs)

Substitute parts are grouped into two categories: direct electrical equivalents with matching peak pulse current (69A) and functional equivalents with reduced peak pulse current (41A–43A) that maintain voltage regulation within acceptable operating ranges.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute (Direct Equivalent): The 1KSMB10A (Taiwan Semiconductor Corporation) is the recommended primary substitute. It maintains identical reverse standoff voltage (8.55V), matching peak pulse current (69A), and equivalent power dissipation (1000W). The part is active in production with ROHS3 compliance and extended operating temperature range (-55 to 175°C). Electrical performance is functionally equivalent with marginally lower clamping voltage (14.5V vs. 15.23V), which remains within acceptable suppression limits for general-purpose applications.

Secondary Substitutes (Functional Equivalents): The SM6T10A-E3/52 (Vishay), SMBJ8.5A (Taiwan Semiconductor), SMBJ8.5A-E3/5B (Vishay), and SMBJ8V5A (Fairchild) are functional equivalents suitable for applications where peak pulse current requirements do not exceed 43A. These parts maintain voltage regulation within 14.4V to 14.5V clamping range and 600W peak pulse power. All are active products with ROHS3 compliance. Selection among secondary substitutes depends on packaging availability, lead time, and cost considerations.

Compliance Verification: All recommended substitutes maintain ROHS3 compliance and unidirectional Zener diode topology. Surface-mount DO-214AA (SMB) package compatibility is confirmed across all alternatives, ensuring direct PCB footprint compatibility without layout modification.

Frequently Asked Questions (FAQ)

Q: Can the 1KSMB10A directly replace the 1KSMB10 without circuit modification? A: Yes. The 1KSMB10A maintains identical reverse standoff voltage (8.55V), peak pulse current (69A), and power dissipation (1000W). The clamping voltage is marginally lower (14.5V vs. 15.23V), which is acceptable for general-purpose overvoltage protection. No circuit modification is required.

Q: What is the difference between direct equivalents and functional equivalents? A: Direct equivalents (1KSMB10A) match the original part's peak pulse current rating (69A) and power dissipation (1000W). Functional equivalents (SM6T10A-E3/52, SMBJ8.5A, SMBJ8.5A-E3/5B, SMBJ8V5A) have reduced peak pulse current (41A–43A) and power dissipation (600W) but maintain voltage regulation within acceptable ranges. Functional equivalents are suitable for applications with lower transient energy requirements.

Q: Are all substitute parts available in the same package? A: Yes. All substitute parts use the DO-214AA (SMB) surface-mount package, ensuring direct PCB footprint compatibility. Packaging format (Tape & Reel, Bulk) may vary by supplier and availability.

Q: Which substitute should be selected for new designs? A: The 1KSMB10A is recommended for new designs due to matching electrical specifications and active production status. If peak pulse current requirements are lower, the SM6T10A-E3/52, SMBJ8.5A, SMBJ8.5A-E3/5B, or SMBJ8V5A are acceptable alternatives with confirmed ROHS3 compliance and active availability.

Q: What is the impact of lower clamping voltage in functional equivalents? A: Functional equivalents clamp at 14.4V to 14.5V compared to the original 15.23V. This represents a 5.4% reduction in clamping voltage, which is acceptable for general-purpose overvoltage suppression. Applications requiring precise voltage regulation at 15.23V should use the direct equivalent 1KSMB10A.

Q: Are there temperature range differences between substitutes? A: Yes. The 1KSMB10A operates to 175°C (vs. 150°C original), providing extended thermal margin. The SM6T10A-E3/52 operates to 150°C. All other substitutes operate within -55 to 150°C. Selection depends on application thermal requirements.