Equivalent & Substitute Parts: 1N5237

Part Overview

The 1N5237 is a Zener diode rated at 8.2 V nominal voltage with 500 mW power dissipation in a DO-35 through-hole package. This component is classified as obsolete, which necessitates identification of active equivalent parts for ongoing design and procurement requirements. The 1N5237 was manufactured by SMC Diode Solutions and is suitable for voltage regulation and protection applications requiring precise 8.2 V reference characteristics.

Substiute Parts

1N5237

SMC Diode SolutionsIn Stock: 51631N5237 Datasheet

Current PartRFQ

1N5237B TR PBFREE

Central Semiconductor CorpIn Stock: 107711N5237B TR PBFREE Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1N5237 is determined by strict equivalence across the following electrical and mechanical parameters:

• Zener Voltage (Vz): 8.2 V nominal
• Power Dissipation: 500 mW maximum
• Impedance (Zzt): 8 Ohms maximum
• Reverse Leakage Current: 3 µA @ 6.5 V
• Forward Voltage: 1.1 V @ 200 mA maximum
• Package Type: DO-35 through-hole axial configuration
• Mounting: Through-hole compatible

The primary substitute identified is the 1N5237B TR PBFREE manufactured by Central Semiconductor Corp. This part maintains electrical equivalence across all critical parameters while offering active product status and enhanced compliance certifications. The 1N5237B TR PBFREE includes a ±5% tolerance specification on the Zener voltage and operates across an extended temperature range of −65°C to 200°C, compared to the original part's maximum operating temperature specification.

Parameter Comparison

Engineering Selection Recommendations

The 1N5237B TR PBFREE is the direct functional equivalent for the obsolete 1N5237. Selection of this substitute is supported by the following factors:

Product Status: The 1N5237B TR PBFREE maintains active product status, ensuring long-term availability and supply chain continuity. The original 1N5237 is obsolete and subject to inventory depletion.

Electrical Equivalence: All critical electrical parameters are identical between the original and substitute part, including Zener voltage, power rating, impedance, reverse leakage current, and forward voltage characteristics. The substitute includes a specified ±5% tolerance on Zener voltage, providing additional design clarity.

Compliance and Certifications: The 1N5237B TR PBFREE is ROHS3 compliant and REACH unaffected, meeting current regulatory requirements for electronic component procurement. Both parts share identical ECCN and HTSUS classifications.

Temperature Performance: The substitute operates across an extended temperature range (−65°C to 200°C) compared to the original specification, providing enhanced thermal margin for applications operating at lower ambient temperatures.

Package Compatibility: Both parts utilize the DO-35 through-hole axial package, ensuring direct mechanical and electrical compatibility in existing circuit board layouts without modification.

Frequently Asked Questions (FAQ)

Q: Can the 1N5237B TR PBFREE be used as a direct replacement for the 1N5237 in existing designs?

A: Yes. The 1N5237B TR PBFREE is electrically and mechanically equivalent to the 1N5237 across all specified parameters. The DO-35 package dimensions are identical, and electrical characteristics match the original part's performance envelope. No circuit modifications are required.

Q: What is the significance of the ±5% tolerance specification on the 1N5237B TR PBFREE?

A: The ±5% tolerance on Zener voltage provides explicit specification of the voltage accuracy range. This tolerance applies to the 8.2 V nominal rating, resulting in an operating range of 7.79 V to 8.61 V. This specification improves design predictability compared to the original part, which did not include a stated tolerance value.

Q: Are there differences in packaging between the 1N5237 and 1N5237B TR PBFREE?

A: Both parts are supplied in DO-35 through-hole axial packages. The 1N5237B TR PBFREE is available in Cut Tape (CT) packaging format, while the original part's packaging format was not specified. The physical component dimensions and pin configuration remain identical.

Q: What compliance advantages does the 1N5237B TR PBFREE offer?

A: The 1N5237B TR PBFREE is ROHS3 compliant, meeting current European Union restrictions on hazardous substances. Both parts are REACH unaffected and share identical export classification codes (ECCN: EAR99, HTSUS: 8541.10.0050).

Q: Is the extended temperature range of the 1N5237B TR PBFREE (−65°C to 200°C) a functional advantage?

A: The extended lower temperature limit provides operational capability in cold environment applications. For designs operating only at or above ambient temperature, this extended range does not alter functional performance but does provide additional thermal margin and design flexibility.

Q: How do the electrical characteristics compare between the two parts?

A: All specified electrical characteristics are identical: 8.2 V Zener voltage, 500 mW power dissipation, 8 Ohms maximum impedance, 3 µA reverse leakage current at 6.5 V, and 1.1 V forward voltage at 200 mA. The substitute part's ±5% tolerance specification provides additional clarity on voltage accuracy.