1N5231B Zener Diode Equivalent & Substitute Parts

Part Overview

The 1N5231B is a through-hole zener diode rated at 5.1 V nominal with 500 mW power dissipation capability, packaged in DO-35 axial configuration. This component is classified as obsolete by the original manufacturer (SMC Diode Solutions), necessitating identification of functionally equivalent alternatives for ongoing design support and procurement requirements. The 1N5231B TR PBFREE variant from Central Semiconductor Corp provides direct functional equivalence with active product status and enhanced compliance certifications.

Substiute Parts

1N5231B

SMC Diode SolutionsIn Stock: 154451N5231B Datasheet

Current PartRFQ

1N5231B TR PBFREE

Central Semiconductor CorpIn Stock: 52421N5231B TR PBFREE Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1N5231B is determined by strict equivalence across the following electrical and mechanical parameters:

Primary Equivalence Criteria:

• Zener voltage: 5.1 V nominal
• Tolerance: ±5%
• Maximum power dissipation: 500 mW
• Package type: DO-35 axial through-hole
• Mounting configuration: Through-hole PCB assembly

Secondary Compatibility Parameters:

• Maximum impedance: 17 Ohms
• Reverse leakage current: 5 µA specification
• Forward voltage: 1.1 V @ 200 mA
• Operating temperature range capability

The 1N5231B TR PBFREE from Central Semiconductor Corp meets all primary and secondary equivalence criteria. This part maintains identical electrical specifications while offering active product status and compliance with ROHS3 and REACH standards. The reverse leakage specification is measured at 2 V instead of 1.9 V, representing a minor measurement condition variation that does not affect functional equivalence.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: 1N5231B TR PBFREE (Central Semiconductor Corp)

This part is the direct functional equivalent of the obsolete 1N5231B. Selection of this substitute is based on:

• Complete electrical parameter equivalence across all specified ratings
• Active product status ensuring long-term availability and supply chain continuity
• ROHS3 compliance certification, meeting current environmental and regulatory standards
• Extended operating temperature range (-65°C to 200°C) providing superior thermal performance margin
• Identical DO-35 axial package configuration enabling direct PCB footprint compatibility
• REACH compliance status matching the original part

The 1N5231B TR PBFREE is supplied in Cut Tape (CT) packaging format, suitable for both manual and automated assembly processes. This substitute eliminates obsolescence risk while maintaining full functional compatibility with existing circuit designs.

Frequently Asked Questions (FAQ)

Q: Can the 1N5231B TR PBFREE be used as a direct replacement for the 1N5231B?

A: Yes. The 1N5231B TR PBFREE provides complete electrical and mechanical equivalence. All critical parameters including zener voltage (5.1 V), power rating (500 mW), tolerance (±5%), and package configuration (DO-35 axial) are identical. The substitute is pin-compatible and requires no circuit modifications.

Q: What is the difference in reverse leakage current specifications?

A: The original 1N5231B specifies 5 µA reverse leakage at 1.9 V, while the 1N5231B TR PBFREE specifies the same 5 µA at 2 V. This represents a minor variation in measurement conditions rather than a functional difference. Both parts meet the same leakage performance requirement.

Q: Does the extended operating temperature range of the substitute affect compatibility?

A: No. The 1N5231B TR PBFREE operates from -65°C to 200°C, compared to the original part's -55°C to 200°C range. The substitute's wider temperature capability provides additional design margin and does not introduce any compatibility issues. Circuits designed for the original part will operate within the substitute's rated range.

Q: Are there packaging format differences between the original and substitute?

A: Both parts use identical DO-35 axial through-hole packaging. The 1N5231B TR PBFREE is supplied in Cut Tape (CT) format, which is standard for automated assembly processes. The physical component dimensions and PCB footprint are identical, enabling direct substitution without layout modifications.

Q: What compliance certifications does the substitute provide?

A: The 1N5231B TR PBFREE is ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements. The original 1N5231B does not specify these certifications, making the substitute the preferred choice for applications requiring documented compliance.

Q: Can the 1N5231B TR PBFREE be used in new designs?

A: Yes. The active product status of the 1N5231B TR PBFREE makes it suitable for both replacement applications and new circuit designs. Its compliance certifications and current manufacturing status ensure long-term availability and supply chain reliability.