SMBJ5377B-TP Zener Diode Equivalent & Substitute Parts

Part Overview

The SMBJ5377B-TP is a 91 V, 5 W surface mount zener diode manufactured by Micro Commercial Co in DO-214AA (SMB) package. This component is classified as an active product with full RoHS3 compliance and unlimited moisture sensitivity rating. Zener diodes of this specification are used in voltage regulation, overvoltage protection, and reference voltage applications in electronic circuits. Substitute parts are identified when equivalent electrical performance can be maintained within the allowed parameter tolerances for the application, or when supply constraints require alternative sourcing from qualified manufacturers.

Substiute Parts

SMBJ5377B-TP

Micro Commercial CoIn Stock: 2138SMBJ5377B-TP Datasheet

Current PartRFQ

SZ1SMB5948BT3G

onsemiIn Stock: 3344SZ1SMB5948BT3G Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of zener diodes is determined by matching the following critical parameters:

1. Zener Voltage (Vz): Must be identical at nominal specification (91 V for this product group)
2. Package / Case Type: Must be DO-214AA (SMB) to ensure mechanical and thermal compatibility with existing PCB layouts
3. Mounting Type: Must be Surface Mount to maintain assembly process compatibility
4. Operating Temperature Range: Must encompass or exceed the application's required temperature envelope
5. RoHS and Compliance Status: Must meet or exceed the regulatory requirements of the primary part

The substitute part SZ1SMB5948BT3G meets the zener voltage, package, and mounting requirements. However, the maximum power rating differs (3 W versus 5 W), and impedance characteristics vary. These differences establish distinct application boundaries and must be evaluated against circuit requirements.

Parameter Comparison

Engineering Selection Recommendations

SMBJ5377B-TP (Primary Part)

The SMBJ5377B-TP is suitable for applications requiring 5 W maximum power dissipation at 91 V zener voltage. This part carries standard industrial qualification and RoHS3 compliance. The ±5% tolerance specification and 75 Ohm maximum impedance provide defined performance boundaries for voltage regulation and protection circuits. Operating temperature range of -55°C to 150°C covers standard industrial and extended commercial applications.

SZ1SMB5948BT3G (Substitute Part)

The SZ1SMB5948BT3G is qualified to AEC-Q101 automotive standards and carries Automotive grade designation. This part is suitable for applications where automotive qualification is required and power dissipation does not exceed 3 W. The extended operating temperature range (-65°C to 150°C) provides additional low-temperature margin. The higher impedance specification (200 Ohms maximum) and increased reverse leakage current (1 µA) represent measurable differences from the primary part and must be evaluated against circuit tolerance requirements.

Substitution Constraints

Direct substitution of SZ1SMB5948BT3G for SMBJ5377B-TP is limited to applications where:

• Maximum power dissipation does not exceed 3 W
• Circuit design accommodates higher impedance (200 Ohms versus 75 Ohms)
• Increased reverse leakage current (1 µA versus 500 nA) is acceptable
• Automotive qualification is not a requirement for the primary part, or automotive qualification is beneficial

Reverse substitution of SMBJ5377B-TP for SZ1SMB5948BT3G is not recommended for automotive applications requiring AEC-Q101 qualification.

Frequently Asked Questions (FAQ)

Q: Can SZ1SMB5948BT3G replace SMBJ5377B-TP in all applications?

A: No. The substitute part has a lower maximum power rating (3 W versus 5 W). Substitution is valid only when circuit power dissipation remains below 3 W. Additionally, the higher impedance and reverse leakage characteristics must be compatible with the circuit design.

Q: What is the significance of the impedance difference between these parts?

A: Impedance (Zzt) affects the dynamic response of the zener diode to transient voltage changes. The SMBJ5377B-TP has 75 Ohm maximum impedance, while the SZ1SMB5948BT3G has 200 Ohm maximum impedance. Higher impedance results in slower transient response and is relevant in high-frequency or fast-transient protection applications.

Q: Are both parts RoHS3 compliant?

A: Yes. Both SMBJ5377B-TP and SZ1SMB5948BT3G carry ROHS3 Compliant status and are suitable for applications with RoHS compliance requirements.

Q: What does AEC-Q101 qualification mean for the SZ1SMB5948BT3G?

A: AEC-Q101 is an automotive industry qualification standard. The SZ1SMB5948BT3G meets this standard, making it suitable for automotive applications. The SMBJ5377B-TP does not carry this designation and should not be assumed to meet automotive qualification requirements.

Q: Do both parts use the same package?

A: Yes. Both parts use DO-214AA (SMB) package and are surface mount components. They are mechanically and thermally compatible with the same PCB footprint and assembly process.

Q: What is the tolerance specification for the SZ1SMB5948BT3G?

A: The tolerance specification is not provided in the available data for the SZ1SMB5948BT3G. The SMBJ5377B-TP specifies ±5% tolerance. This difference should be clarified with the manufacturer when tolerance is a critical circuit parameter.

Q: Can SMBJ5377B-TP be used in place of SZ1SMB5948BT3G in automotive applications?

A: No. The SMBJ5377B-TP does not carry AEC-Q101 automotive qualification. Automotive applications requiring qualified components must use the SZ1SMB5948BT3G or equivalent automotive-qualified alternatives.

Q: What is the difference in reverse leakage current between these parts?

A: The SMBJ5377B-TP specifies 500 nA reverse leakage at 69.2 V, while the SZ1SMB5948BT3G specifies 1 µA at the same voltage. The substitute part has approximately 2 times higher leakage current. This difference is relevant in precision voltage reference and low-power standby applications.