1N5255 Zener Diode Equivalent & Substitute Parts

Part Overview

The 1N5255 is a through-hole zener diode rated for 28 V nominal zener voltage with 500 mW maximum power dissipation in a DO-35 axial package. This component is classified as obsolete, making identification of active equivalent parts essential for ongoing design support and procurement continuity. The substitute part 1N5255B TR PBFREE maintains identical electrical specifications while offering active product status and expanded temperature operating range.

Substiute Parts

1N5255

SMC Diode SolutionsIn Stock: 11711N5255 Datasheet

Current PartRFQ

1N5255B TR PBFREE

Central Semiconductor CorpIn Stock: 219251N5255B TR PBFREE Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 1N5255 with the 1N5255B TR PBFREE is valid based on the following electrical and mechanical parameter alignment:

Matching Parameters:

• Zener voltage: 28 V nominal (identical specification)
• Maximum power dissipation: 500 mW (identical specification)
• Impedance (Max): 44 Ohms (identical specification)
• Reverse leakage current: 100 nA @ 21 V (identical specification)
• Forward voltage: 1.1 V @ 200 mA (identical specification)
• Package type: DO-35 axial through-hole (identical mechanical form factor)
• Moisture sensitivity: MSL 1 (Unlimited) (identical classification)

Distinguishing Factors:

• 1N5255B TR PBFREE includes ±5% zener voltage tolerance specification
• 1N5255B TR PBFREE operates across extended temperature range: -65°C to 200°C
• 1N5255B TR PBFREE maintains active product status with RoHS3 compliance
• 1N5255B TR PBFREE is lead-free (PBFREE designation)

Parameter Comparison

Engineering Selection Recommendations

The 1N5255B TR PBFREE is a direct electrical and mechanical substitute for the obsolete 1N5255. Selection of the 1N5255B TR PBFREE is supported by the following factors:

Electrical Compatibility: All critical electrical parameters match the original specification: 28 V zener voltage, 500 mW power rating, 44 Ohms impedance, and identical leakage and forward voltage characteristics.

Mechanical Compatibility: Both components use identical DO-35 axial through-hole packaging, ensuring direct board-level substitution without layout modification.

Product Status: The 1N5255B TR PBFREE maintains active product status, ensuring long-term availability and supply chain continuity compared to the obsolete 1N5255.

Regulatory Compliance: The 1N5255B TR PBFREE is RoHS3 compliant and lead-free, meeting current environmental and manufacturing standards. Both parts maintain REACH Unaffected status and identical ECCN and HTSUS classifications.

Temperature Performance: The 1N5255B TR PBFREE provides an extended operating temperature range (-65°C to 200°C) compared to the 1N5255 specification, offering improved performance margin in temperature-sensitive applications.

Tolerance Specification: The 1N5255B TR PBFREE includes explicit ±5% zener voltage tolerance, providing defined performance boundaries for circuit design.

Frequently Asked Questions (FAQ)

Q: Can the 1N5255B TR PBFREE be used as a direct replacement for the 1N5255 in existing designs?

A: Yes. The 1N5255B TR PBFREE is electrically and mechanically compatible with the 1N5255. All critical electrical parameters are identical, and both components use the same DO-35 axial through-hole package. No circuit modifications or board redesign are required.

Q: What is the significance of the "PBFREE" designation in the 1N5255B TR PBFREE part number?

A: PBFREE indicates that the component is manufactured without lead (Pb), meeting RoHS3 compliance requirements. This designation reflects current manufacturing standards and environmental regulations.

Q: Does the extended temperature range of the 1N5255B TR PBFREE affect circuit performance?

A: The 1N5255B TR PBFREE operates from -65°C to 200°C, compared to the 1N5255 specification of 200°C maximum. The extended lower temperature limit provides additional operational margin. All electrical characteristics remain consistent across the specified temperature range.

Q: Are there packaging differences between the 1N5255 and 1N5255B TR PBFREE?

A: No. Both components are supplied in DO-35 axial through-hole packages. The 1N5255B TR PBFREE is supplied in Cut Tape (CT) packaging format, which is standard for active production components.

Q: What is the tolerance specification for the 1N5255B TR PBFREE zener voltage?

A: The 1N5255B TR PBFREE has a zener voltage tolerance of ±5% at the 28 V nominal specification. This tolerance specification is not provided for the obsolete 1N5255.

Q: Are the electrical characteristics identical between the two parts?

A: Yes. The zener voltage (28 V), maximum power dissipation (500 mW), impedance (44 Ohms), reverse leakage current (100 nA @ 21 V), and forward voltage (1.1 V @ 200 mA) are identical between the 1N5255 and 1N5255B TR PBFREE.

Q: What regulatory certifications apply to the 1N5255B TR PBFREE?

A: The 1N5255B TR PBFREE is RoHS3 compliant, REACH Unaffected, and classified under ECCN EAR99 and HTSUS 8541.10.0050, matching the regulatory classification of the original 1N5255.