SMBJ120C Transient Voltage Suppressor Diode - Equivalent & Substitute Parts

Part Overview

The SMBJ120C is a bidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection in surface-mount applications. The device features a 120V reverse standoff voltage with a 202.65V maximum clamping voltage and 3.1A peak pulse current capability in a DO-214AA (SMB) package. The SMBJ120C is classified as obsolete, necessitating identification of active equivalent alternatives that maintain electrical and mechanical compatibility for ongoing production and repair applications.

Substiute Parts

SMBJ120C

Littelfuse Inc.In Stock: 1082SMBJ120C Datasheet

Current PartRFQ

SMBJ120CA

MeritekIn Stock: 34486SMBJ120CA Datasheet

MFR RecommendedRFQ

SMBJ120CA

MeritekIn Stock: 34486SMBJ120CA Datasheet

MFR RecommendedRFQ

SMBJ120CA

MeritekIn Stock: 34486SMBJ120CA Datasheet

MFR RecommendedRFQ

SMBJ120CA-13-F

Diodes IncorporatedIn Stock: 3955SMBJ120CA-13-F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMBJ120C is determined by strict alignment of the following electrical and mechanical parameters:

Critical Substitution Parameters:

• Reverse Standoff Voltage: 120V (Typ)
• Bidirectional Channels: 1
• Package / Case: DO-214AA (SMB)
• Mounting Type: Surface Mount
• Series: SMBJ
• Type: Zener

Acceptable Variation Parameters:

• Voltage - Breakdown (Min): Range 126V to 133V
• Voltage - Clamping (Max) @ Ipp: Range 193V to 202.65V
• Current - Peak Pulse (10/1000µs): Range 3.1A to 3.11A
• Power - Peak Pulse: 600W (fixed)
• Operating Temperature: -55°C to -65°C minimum; 150°C maximum
• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity Level (MSL): 1 (Unlimited)

All identified substitute parts maintain the SMBJ series designation, single bidirectional channel configuration, and DO-214AA SMB package specification. Electrical parameters remain within acceptable tolerances for general-purpose transient voltage suppression applications.

Parameter Comparison

Engineering Selection Recommendations

SMBJ120CA (Meritek) and SMBJ120CA-13-F (Diodes Incorporated) are direct functional equivalents to the obsolete SMBJ120C. Both substitute parts maintain active product status, ensuring long-term availability and supply chain continuity.

Selection between the two active alternatives is based on packaging and inventory requirements:

SMBJ120CA (Meritek): Available in bulk form with 34,400 units in stock. Suitable for high-volume production runs and applications where tape and reel packaging is not required.

SMBJ120CA-13-F (Diodes Incorporated): Supplied in Tape & Reel (TR) packaging with 3,900 units in stock. Recommended for automated assembly processes and applications requiring standard SMT reel formats.

Both parts comply with ROHS3 regulations, maintain MSL 1 (Unlimited) moisture sensitivity classification, and operate across the required temperature range. The clamping voltage differential (193V versus 202.65V) and breakdown voltage variation (133V versus 126V) remain within acceptable engineering tolerances for general-purpose transient voltage suppression.

Frequently Asked Questions (FAQ)

Q: Can SMBJ120CA and SMBJ120CA-13-F be used interchangeably with SMBJ120C?

A: Yes. Both parts maintain identical reverse standoff voltage (120V), bidirectional channel configuration (1), and DO-214AA SMB package specification. Electrical parameters fall within acceptable substitution tolerances for general-purpose TVS applications.

Q: What is the difference between SMBJ120CA and SMBJ120CA-13-F?

A: The primary difference is packaging format. SMBJ120CA is supplied in bulk, while SMBJ120CA-13-F is supplied in Tape & Reel (TR) format. Electrical specifications are equivalent. Selection depends on assembly process requirements and inventory management practices.

Q: Why does the clamping voltage differ between the main part and substitutes?

A: SMBJ120C specifies a maximum clamping voltage of 202.65V, while both SMBJ120CA variants specify 193V. This 9.65V difference remains within acceptable engineering tolerance for transient voltage suppression and does not affect functional compatibility in general-purpose applications.

Q: Are there temperature range considerations when substituting?

A: SMBJ120C operates from -65°C to 150°C, while both substitute parts operate from -55°C to 150°C. The substitute parts have a narrower minimum temperature specification. Applications requiring operation below -55°C require design review.

Q: Do all parts meet RoHS compliance requirements?

A: Yes. SMBJ120C, SMBJ120CA, and SMBJ120CA-13-F are all ROHS3 compliant with MSL 1 (Unlimited) moisture sensitivity classification.

Q: Which substitute part should be selected for new designs?

A: Both SMBJ120CA and SMBJ120CA-13-F are active products suitable for new designs. Selection is based on manufacturing process requirements: SMBJ120CA for manual or bulk assembly, SMBJ120CA-13-F for automated SMT processes.