1N5243B Zener Diode Equivalent & Substitute Parts

Part Overview

The 1N5243B is a through-hole zener diode rated at 13 V nominal with 500 mW power dissipation and ±5% tolerance. Manufactured by SMC Diode Solutions, this component is classified as obsolete. Due to its obsolete status and limited availability from the original manufacturer, identifying equivalent substitute parts is necessary to maintain design continuity and ensure supply chain reliability for applications requiring 13 V zener regulation in DO-35 axial packages.

Substiute Parts

1N5243B

SMC Diode SolutionsIn Stock: 31631N5243B Datasheet

Current PartRFQ

1N5243B TR PBFREE

Central Semiconductor CorpIn Stock: 107251N5243B TR PBFREE Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1N5243B is determined by strict equivalence across the following electrical and mechanical parameters:

Critical Substitution Criteria:

• Zener voltage (Vz): 13 V nominal
• Tolerance: ±5%
• Power rating: 500 mW maximum
• Impedance (Zzt): 13 Ohms maximum
• Reverse leakage current: 500 nA @ specified reverse voltage
• Forward voltage: 1.1 V maximum @ 200 mA
• Package type: DO-35 axial through-hole configuration
• Mounting: Through-hole compatible

The substitute part 1N5243B TR PBFREE, manufactured by Central Semiconductor Corp, meets all electrical specifications and mechanical requirements. This part maintains identical zener voltage, tolerance, power dissipation, impedance, and forward voltage characteristics. The primary distinction is product status: the substitute is active and in production, whereas the original is obsolete. The substitute also provides expanded operating temperature range and RoHS3 compliance, offering improved supply availability and regulatory alignment.

Parameter Comparison

Engineering Selection Recommendations

The 1N5243B TR PBFREE from Central Semiconductor Corp is a direct electrical and mechanical equivalent to the obsolete 1N5243B. Selection of this substitute is based on the following engineering factors:

Product Status: The substitute is actively manufactured and in production, eliminating supply chain risk associated with the obsolete original part.

Electrical Equivalence: All critical electrical parameters—zener voltage, tolerance, power dissipation, impedance, reverse leakage, and forward voltage—are identical to the original specification.

Mechanical Compatibility: Both parts utilize the DO-35 axial through-hole package, ensuring direct board-level compatibility without circuit redesign or PCB modification.

Regulatory Compliance: The substitute carries RoHS3 compliance certification, meeting current environmental and regulatory requirements. Both parts maintain REACH Unaffected status and identical ECCN and HTSUS classifications.

Operating Temperature: The substitute provides an expanded operating temperature range (-65°C to 200°C) compared to the original specification, offering enhanced performance margin in temperature-sensitive applications.

Packaging Format: The substitute is supplied in Cut Tape (CT) format, standard for production environments, with significantly higher inventory availability (10,653 pieces in stock versus 3,100 for the original).

Frequently Asked Questions (FAQ)

Q: Can the 1N5243B TR PBFREE be used as a direct replacement for the 1N5243B?

A: Yes. The 1N5243B TR PBFREE is electrically and mechanically equivalent. All electrical parameters—zener voltage (13 V), tolerance (±5%), power rating (500 mW), impedance (13 Ohms), reverse leakage (500 nA), and forward voltage (1.1 V @ 200 mA)—are identical. The DO-35 axial through-hole package is the same, enabling direct board-level substitution without circuit modification.

Q: Why is the original 1N5243B listed as obsolete?

A: The 1N5243B from SMC Diode Solutions has reached end-of-life status and is no longer in active production. While limited inventory remains available (3,100 pieces), the substitute from Central Semiconductor Corp is actively manufactured, ensuring long-term supply availability.

Q: What is the difference between the two parts?

A: The primary differences are manufacturer, product status, and operating temperature range. The substitute is actively produced by Central Semiconductor Corp, carries RoHS3 compliance, and offers an expanded operating temperature range (-65°C to 200°C) versus the original specification. All electrical and mechanical specifications are identical.

Q: Does the substitute require any circuit design changes?

A: No. The 1N5243B TR PBFREE maintains identical electrical characteristics and the same DO-35 axial package configuration. No circuit redesign, PCB layout modification, or application firmware changes are required.

Q: What is the packaging difference between the two parts?

A: The original 1N5243B is supplied in standard packaging, while the substitute (1N5243B TR PBFREE) is supplied in Cut Tape (CT) format. Both are through-hole components with identical physical dimensions and pin configuration. Cut Tape format is standard for automated assembly environments.

Q: Are there any compliance or certification differences?

A: The substitute carries RoHS3 compliance certification, meeting current environmental regulations. Both parts maintain REACH Unaffected status and identical ECCN (EAR99) and HTSUS (8541.10.0050) classifications, ensuring regulatory alignment for export and procurement purposes.

Q: What is the reverse leakage current specification difference?

A: The original specifies 500 nA @ 9.4 V, while the substitute specifies 500 nA @ 9.9 V. Both meet the 500 nA maximum leakage criterion. The slight difference in test voltage does not affect functional equivalence or circuit performance.