P6SMBJ27 Transient Voltage Suppressor Equivalent & Substitute Parts

Part Overview

The P6SMBJ27 is a unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc. in the DO-214AA (SMB) surface mount package. This component is designed for general-purpose transient voltage suppression applications with a reverse standoff voltage of 23.1V and peak pulse power rating of 600W. The part is currently obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement.

Substiute Parts

P6SMBJ27

Littelfuse Inc.In Stock: 678P6SMBJ27 Datasheet

Current PartRFQ

SZP6SMB27AT3G

onsemiIn Stock: 2160SZP6SMB27AT3G Datasheet

MFR RecommendedRFQ

SMBJP6KE27A-TP

Micro Commercial CoIn Stock: 1190SMBJP6KE27A-TP Datasheet

DirectRFQ

P6SMB27A

Eaton - Electronics DivisionIn Stock: 20240P6SMB27A Datasheet

MFR RecommendedRFQ

SM6T27A

STMicroelectronicsIn Stock: 10481SM6T27A Datasheet

MFR RecommendedRFQ

SM6T27A-E3/52

Vishay General Semiconductor - Diodes DivisionIn Stock: 8572SM6T27A-E3/52 Datasheet

MFR RecommendedRFQ

SM6T27A-E3/5B

Vishay General Semiconductor - Diodes DivisionIn Stock: 923SM6T27A-E3/5B Datasheet

MFR RecommendedRFQ

SM6T27AY

STMicroelectronicsIn Stock: 7176SM6T27AY Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the P6SMBJ27 is determined by the following critical parameters:

• Voltage - Reverse Standoff (Typ): 23.1V (all substitutes must match)
• Voltage - Breakdown (Min): 24.35V minimum (substitutes range from 25.7V, which is acceptable as it exceeds minimum)
• Unidirectional Channels: 1 (single channel requirement)
• Mounting Type: Surface Mount
• Package / Case: DO-214AA, SMB (physical and electrical compatibility)
• Power - Peak Pulse: 600W (all substitutes maintain this rating)
• Type: Zener (all substitutes are Zener type)

Substitute parts are grouped into two categories based on clamping voltage performance:

Group A - Lower Clamping Voltage (37.5V): SZP6SMB27AT3G, SMBJP6KE27A-TP, P6SMB27A, SM6T27A-E3/52, SM6T27A-E3/5B. These parts provide tighter voltage clamping closer to the original specification.

Group B - Higher Clamping Voltage (48.3V): SM6T27A, SM6T27AY. These parts offer higher clamping voltage with increased peak pulse current capability (83A vs 16.3A), suitable for applications requiring enhanced transient suppression.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Lowest Risk):

P6SMB27A (Eaton - Electronics Division) is the primary recommendation. This part maintains identical electrical specifications to the original P6SMBJ27, including 37.5V clamping voltage and 16.3A peak pulse current. It is in active production status with RoHS compliance and the largest available inventory (20,140 pcs), ensuring long-term supply continuity.

For Automotive Applications:

SZP6SMB27AT3G (onsemi) or SM6T27AY (STMicroelectronics) are qualified to AEC-Q101 automotive standards. Both maintain the 23.1V reverse standoff voltage and 600W power rating. SZP6SMB27AT3G provides 37.5V clamping voltage matching Group A specifications, while SM6T27AY offers 48.3V clamping with enhanced current handling (83A).

For Extended Temperature Range:

SMBJP6KE27A-TP (Micro Commercial Co) supports operating temperatures from -55°C to 175°C, exceeding the original specification range. This part maintains 37.5V clamping voltage and 16.3A peak pulse current with ROHS3 compliance.

For Enhanced Transient Suppression:

SM6T27A or SM6T27AY (STMicroelectronics) provide 48.3V clamping voltage with significantly higher peak pulse current (83A at 8/20µs pulse). These parts are suitable for applications requiring superior transient energy absorption while maintaining the 23.1V reverse standoff voltage and 600W power rating.

Frequently Asked Questions (FAQ)

Q: Can I use SM6T27A or SM6T27AY as direct replacements for P6SMBJ27?

A: These parts share the same reverse standoff voltage (23.1V), breakdown voltage (25.7V), power rating (600W), and package (DO-214AA, SMB). However, they feature higher clamping voltage (48.3V vs 39.38V) and significantly higher peak pulse current (83A vs 16.3A). They are functionally compatible but provide enhanced suppression capability. Circuit validation is necessary to confirm suitability for your specific application.

Q: What is the difference between Group A and Group B substitutes?

A: Group A substitutes (37.5V clamping) provide performance closer to the original P6SMBJ27 (39.38V clamping) with comparable peak pulse current ratings (16A-16.3A). Group B substitutes (48.3V clamping) offer higher voltage clamping and substantially increased peak pulse current (83A), making them suitable for applications requiring enhanced transient protection.

Q: Are all substitute parts RoHS compliant?

A: All listed substitutes are RoHS compliant. Most are ROHS3 compliant. SZP6SMB27AT3G compliance status is not specified in the provided data.

Q: Which substitute offers the best long-term availability?

A: P6SMB27A (Eaton - Electronics Division) has the highest current inventory (20,140 pcs) and active production status, providing the strongest supply assurance for ongoing procurement.

Q: Can I use automotive-grade substitutes in non-automotive applications?

A: Yes. Automotive-grade parts (SZP6SMB27AT3G with AEC-Q101 and SM6T27AY with AEC-Q101) meet or exceed the electrical and reliability requirements for general-purpose applications. Their automotive qualification represents additional quality assurance.

Q: What is the impact of different clamping voltages on circuit performance?

A: Clamping voltage determines the maximum voltage the TVS diode allows across the protected circuit during transient events. Lower clamping voltage (37.5V in Group A) provides tighter voltage regulation closer to the original specification. Higher clamping voltage (48.3V in Group B) allows slightly higher transient voltages but with greater current absorption capability. Selection depends on the protected circuit's voltage tolerance.

Q: Are the package dimensions identical across all substitutes?

A: All substitutes use the DO-214AA (SMB) surface mount package, ensuring identical PCB footprint and mounting compatibility. Physical placement and reflow parameters remain unchanged.