SMBJE28AH Equivalent & Substitute Parts

Part Overview

The SMBJE28AH is an automotive-grade transient voltage suppressor (TVS) diode manufactured by Eaton - Electronics Division. This unidirectional zener diode is designed for surface mount applications in telecom protection circuits, featuring a 28V reverse standoff voltage and 45.4V maximum clamping voltage. The device is housed in a DO-214AA (SMB) package and is qualified to AEC-Q101 automotive standards. The SMBJE28AH maintains active product status with ROHS3 compliance and unlimited moisture sensitivity rating. Equivalent and substitute parts are identified to support design flexibility, inventory optimization, and supply chain continuity for applications requiring identical or functionally compatible transient voltage suppression characteristics.

Substiute Parts

SMBJE28AH

Eaton - Electronics DivisionIn Stock: 4172SMBJE28AH Datasheet

Current PartRFQ

P6SMB33A-Q

Bourns Inc.In Stock: 9922P6SMB33A-Q Datasheet

SimilarRFQ

SM6T33AY

STMicroelectronicsIn Stock: 57473SM6T33AY Datasheet

SimilarRFQ

SMBJ28A-Q

Bourns Inc.In Stock: 1839SMBJ28A-Q Datasheet

SimilarRFQ

SZ1SMB28AT3G

Littelfuse Inc.In Stock: 144063SZ1SMB28AT3G Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SMBJE28AH is determined by electrical and mechanical parameter compatibility within the transient voltage suppressor category. The critical parameters governing substitution are:

Voltage Parameters: Reverse standoff voltage (28V nominal), breakdown voltage minimum (31.1V), and maximum clamping voltage (45.4V) establish the protection threshold and response characteristics. Substitute parts must maintain equivalent or tighter voltage specifications to ensure proper circuit protection without exceeding design limits.

Current and Power Ratings: Peak pulse current (13.2A at 10/1000µs) and peak pulse power (600W) define the device's transient energy handling capacity. Substitute parts must meet or exceed these ratings to provide equivalent protection performance.

Package and Mounting: All substitute parts utilize the DO-214AA (SMB) surface mount package, ensuring mechanical and electrical compatibility with existing PCB layouts and assembly processes.

Automotive Compliance: All substitute parts maintain AEC-Q101 qualification and automotive-grade designation, preserving reliability and qualification status for automotive applications.

Environmental and Regulatory Compliance: ROHS3 compliance, unlimited MSL rating, and REACH unaffected status are maintained across all substitute options.

Parameter Comparison

Engineering Selection Recommendations

Direct Equivalents (Preferred Substitutes):

The SMBJ28A-Q (Bourns Inc.) and SZ1SMB28AT3G (Littelfuse Inc.) are direct electrical equivalents to the SMBJE28AH. Both devices maintain identical reverse standoff voltage (28V), breakdown voltage (31.1V), clamping voltage (45.4V), and peak pulse current (13.2A to 13.3A). All three parts share automotive-grade designation, AEC-Q101 qualification, ROHS3 compliance, and unlimited MSL rating. These substitutes are suitable for one-to-one replacement in existing designs without circuit modification.

Compatible Substitutes (Functionally Equivalent):

The P6SMB33A-Q (Bourns Inc.) provides functional equivalence with marginally higher voltage specifications (28.2V standoff, 31.4V breakdown, 45.7V clamping) and peak pulse current (13.3A). The device maintains all automotive compliance requirements and is suitable for applications where slightly elevated clamping voltage is acceptable.

Application-Specific Consideration:

The SM6T33AY (STMicroelectronics) exhibits higher clamping voltage (59V) and significantly elevated peak pulse current (68A at 8/20µs pulse width). This device is suitable only for applications requiring enhanced transient energy absorption beyond the SMBJE28AH specification. The different pulse width specification (8/20µs versus 10/1000µs) indicates different transient response characteristics and should be evaluated against specific circuit requirements.

Compliance and Qualification Status:

All substitute parts maintain active product status and automotive-grade qualification. The SMBJ28A-Q carries REACH Affected status, while the SMBJE28AH, P6SMB33A-Q, SM6T33AY, and SZ1SMB28AT3G are REACH Unaffected. Regulatory compliance requirements should be verified for specific applications.

Frequently Asked Questions (FAQ)

Q: Can the P6SMB33A-Q replace the SMBJE28AH in all applications?

A: The P6SMB33A-Q is functionally compatible with the SMBJE28AH for most telecom protection applications. The slightly higher clamping voltage (45.7V versus 45.4V) and breakdown voltage (31.4V versus 31.1V) remain within acceptable tolerance for standard circuit protection. Verification against specific circuit design limits is required for applications with tight voltage constraints.

Q: What is the difference between the SM6T33AY and other substitute options?

A: The SM6T33AY differs in two critical parameters: clamping voltage (59V versus 45.4V) and peak pulse current (68A at 8/20µs versus 13.2A at 10/1000µs). The higher clamping voltage and current rating indicate this device is designed for higher-energy transient suppression. The different pulse width specification reflects different transient waveform characteristics. This device is suitable only for applications requiring enhanced protection beyond the SMBJE28AH specification.

Q: Are all substitute parts compatible with existing PCB layouts?

A: All substitute parts utilize the DO-214AA (SMB) surface mount package, ensuring mechanical and electrical compatibility with PCB layouts designed for the SMBJE28AH. No PCB redesign or assembly process modification is required for package-compatible substitutes.

Q: What is the significance of AEC-Q101 qualification?

A: AEC-Q101 qualification certifies that the device meets automotive industry reliability and quality standards established by the Automotive Electronics Council. All listed substitute parts maintain this qualification, ensuring equivalent reliability performance for automotive applications.

Q: Does operating temperature range affect substitution decisions?

A: The SMBJE28AH operates from -55°C to 150°C, while the SZ1SMB28AT3G extends to -65°C minimum. For applications operating below -55°C, the SZ1SMB28AT3G provides extended temperature coverage. For standard automotive applications within the -55°C to 150°C range, all substitute parts are equivalent.

Q: What is the importance of RoHS3 compliance and MSL rating?

A: ROHS3 compliance certifies that the device contains no restricted hazardous substances, meeting environmental regulatory requirements for electronic components. Unlimited MSL (Moisture Sensitivity Level 1) rating indicates the device requires no special moisture control during storage, handling, or assembly, simplifying supply chain management and manufacturing processes.

Q: Can the SMBJ28A-Q be used as a direct replacement for the SMBJE28AH?

A: The SMBJ28A-Q is a direct electrical equivalent with identical voltage and current specifications. The primary difference is REACH status (REACH Affected versus REACH Unaffected). For applications subject to REACH regulations, regulatory compliance requirements should be verified before substitution.