1N5238B Zener Diode Equivalent & Substitute Parts

Part Overview

The 1N5238B is a through-hole zener diode rated at 8.7 V nominal with 500 mW power dissipation capability, packaged in the 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 continuity. The substitute part maintains identical electrical specifications while offering active product status and improved availability.

Substiute Parts

1N5238B

SMC Diode SolutionsIn Stock: 32071N5238B Datasheet

Current PartRFQ

1N5238B TR PBFREE

Central Semiconductor CorpIn Stock: 100191N5238B TR PBFREE Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1N5238B is based on electrical and mechanical parameter equivalence within the zener diode category. The substitute part 1N5238B TR PBFREE (Central Semiconductor Corp) qualifies as a direct equivalent because it maintains all critical electrical specifications: identical nominal zener voltage (8.7 V), tolerance (±5%), maximum power rating (500 mW), maximum impedance (8 Ohms), and forward voltage characteristic (1.1 V @ 200 mA). Both components utilize the DO-35 axial through-hole package, ensuring mechanical and PCB-level compatibility.

The substitution logic is based on the following key parameters:

• Voltage - Zener (Nom): 8.7 V (exact match required)
• Tolerance: ±5% (exact match required)
• Power - Max: 500 mW (exact match required)
• Impedance (Max): 8 Ohms (exact match required)
• Package / Case: DO-35, Axial (exact match required)
• Mounting Type: Through Hole (exact match required)

The substitute part differs in product status (active vs. obsolete), operating temperature range, and compliance certifications, but these differences do not affect functional substitutability in applications designed for the original 1N5238B specification.

Parameter Comparison

Engineering Selection Recommendations

The 1N5238B TR PBFREE (Central Semiconductor Corp) is the direct functional equivalent for applications currently specified with the 1N5238B. Selection of this substitute is supported by the following engineering factors:

Electrical Equivalence: All critical electrical parameters match the original specification exactly, including zener voltage (8.7 V), tolerance (±5%), power rating (500 mW), and impedance (8 Ohms). Reverse leakage current specifications are functionally equivalent despite measurement at slightly different reference voltages (6.2 V vs. 6.5 V).

Mechanical Compatibility: Both components use the DO-35 axial through-hole package, ensuring direct PCB-level compatibility without layout modifications.

Product Status and Availability: The substitute part carries active product status with 9,950 units in stock, compared to the obsolete original with 3,100 units. This availability differential supports long-term procurement continuity.

Compliance and Certifications: The substitute part is ROHS3 compliant and carries REACH Unaffected status, meeting current regulatory requirements. Both components share identical ECCN (EAR99) and HTSUS (8541.10.0050) classifications.

Operating Temperature: The substitute part offers an extended operating temperature range (-65°C ~ 200°C) compared to the original specification (200°C maximum), providing additional thermal margin in applications with low-temperature exposure requirements.

Frequently Asked Questions (FAQ)

Q: Can the 1N5238B TR PBFREE be used as a direct replacement for the 1N5238B in existing designs?

A: Yes. The substitute part maintains identical electrical specifications (8.7 V nominal zener voltage, ±5% tolerance, 500 mW power rating, 8 Ohms impedance) and uses the same DO-35 axial through-hole package. No circuit modifications or PCB layout changes are required.

Q: What is the primary reason for substitution?

A: The original 1N5238B is classified as obsolete by SMC Diode Solutions. The substitute part (1N5238B TR PBFREE) is manufactured by Central Semiconductor Corp with active product status and significantly higher inventory availability, ensuring procurement continuity.

Q: Are there any differences in electrical performance between the original and substitute parts?

A: All primary electrical specifications are identical. The reverse leakage current is measured at slightly different reference voltages (6.2 V vs. 6.5 V), but both specifications yield functionally equivalent performance. The substitute part offers an extended operating temperature range (-65°C ~ 200°C vs. 200°C maximum), which provides additional thermal capability.

Q: Does the substitute part meet current regulatory requirements?

A: Yes. The 1N5238B TR PBFREE is ROHS3 compliant and carries REACH Unaffected status. Both the original and substitute parts share identical ECCN (EAR99) and HTSUS (8541.10.0050) classifications.

Q: Is the packaging format identical between the two parts?

A: Yes. Both components use the DO-35 axial through-hole package (DO-204AH designation). Physical dimensions and lead configuration are identical, ensuring direct PCB compatibility without rework.

Q: What is the moisture sensitivity level for the substitute part?

A: The substitute part carries MSL 1 (Unlimited), indicating no moisture sensitivity restrictions. This matches the original part specification and allows standard handling and storage procedures.

Q: Are there any inventory or lead time advantages to using the substitute part?

A: Yes. The substitute part has 9,950 units in stock compared to 3,100 units for the original. The substitute is supplied in Cut Tape (CT) packaging format, which may offer additional handling flexibility for automated assembly processes.