1KSMB11C Equivalent & Substitute Parts

Part Overview

The 1KSMB11C is a Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose transient voltage protection in surface-mount applications. This bidirectional Zener diode operates with a reverse standoff voltage of 9.4V and provides clamping at 16.38V maximum. The part is currently classified as obsolete, making equivalent substitute parts necessary for ongoing design support and procurement.

Substiute Parts

1KSMB11C

Littelfuse Inc.In Stock: 9871KSMB11C Datasheet

Current PartRFQ

1KSMB11CA

Taiwan Semiconductor CorporationIn Stock: 302151KSMB11CA Datasheet

DirectRFQ

P6SMB11CA

Eaton - Electronics DivisionIn Stock: 2357P6SMB11CA Datasheet

MFR RecommendedRFQ

SMBJP6KE11CA-TP

Micro Commercial CoIn Stock: 4489SMBJP6KE11CA-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1KSMB11C is determined by the following critical parameters that must remain consistent across equivalent parts:

Core Electrical Parameters (Must Match):

• Voltage - Reverse Standoff (Typ): 9.4V
• Voltage - Breakdown (Min): 9.95V to 10.5V range
• Bidirectional Channels: 1
• Type: Zener

Mechanical & Package Parameters (Must Match):

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

Performance Parameters (Acceptable Variation):

• Voltage - Clamping (Max) @ Ipp: 15.6V to 16.38V
• Current - Peak Pulse (10/1000µs): 39.1A to 64.1A
• Power - Peak Pulse: 600W to 1000W

The substitute parts listed below maintain compatibility within these parameter boundaries while offering active product status and improved availability.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: 1KSMB11CA

The 1KSMB11CA from Taiwan Semiconductor Corporation is the closest functional equivalent to the 1KSMB11C. This part maintains identical reverse standoff voltage (9.4V), peak pulse current (64.1A), and peak pulse power (1000W). The clamping voltage is reduced to 15.6V, which provides improved transient suppression performance. The part carries active product status with substantial inventory availability (30,200 pcs) and ROHS3 compliance. Extended operating temperature range (-55°C ~ 175°C) provides additional thermal margin compared to the original part.

Secondary Substitutes: P6SMB11CA and SMBJP6KE11CA-TP

Both P6SMB11CA (Eaton) and SMBJP6KE11CA-TP (Micro Commercial Co) maintain the 9.4V reverse standoff voltage and 15.6V clamping voltage. These parts feature reduced peak pulse current (39.1A) and power dissipation (600W) compared to the main part. Selection of these alternatives is appropriate for applications where the lower current and power ratings are sufficient. Both parts are active products with RoHS compliance and adequate inventory levels.

Compliance Considerations

All substitute parts maintain ROHS3 or RoHS compliance status, ensuring regulatory alignment with the original 1KSMB11C specification. REACH compliance is confirmed for all active substitute options.

Frequently Asked Questions (FAQ)

Q: Can the 1KSMB11CA directly replace the 1KSMB11C without circuit modification?

A: Yes. The 1KSMB11CA maintains the same reverse standoff voltage (9.4V), package type (DO-214AA, SMB), and mounting configuration. The reduced clamping voltage (15.6V vs 16.38V) provides improved transient suppression without requiring circuit changes.

Q: What is the difference between the 1KSMB11CA and P6SMB11CA?

A: Both parts share the same 9.4V reverse standoff and 15.6V clamping voltage. The primary difference is peak pulse current rating: 1KSMB11CA provides 64.1A while P6SMB11CA provides 39.1A. Selection depends on the application's transient current requirements. The 1KSMB11CA is recommended for higher-current transient environments.

Q: Are all substitute parts available in the same package?

A: Yes. All substitute parts use the DO-214AA (SMB) surface-mount package, ensuring mechanical and electrical compatibility with the original 1KSMB11C footprint.

Q: Which substitute offers the best thermal performance?

A: The 1KSMB11CA and SMBJP6KE11CA-TP both support extended operating temperature ranges up to 175°C, compared to 150°C for the original part and P6SMB11CA. This provides additional thermal margin in high-temperature applications.

Q: Is the 1KSMB11C still available for procurement?

A: The 1KSMB11C is classified as obsolete. While limited inventory (896 pcs) may be available through legacy stock channels, active substitute parts are recommended for new designs and ongoing procurement to ensure long-term supply chain stability.