BZX79C22 Equivalent & Substitute Parts

Part Overview

The BZX79C22 is a 22 V, 500 mW Zener diode manufactured by onsemi in a through-hole DO-35 package. This component is classified as obsolete, necessitating identification of active equivalent and substitute parts for ongoing design requirements and procurement needs. Equivalent parts maintain identical electrical specifications, while substitute parts provide functional alternatives with modified performance characteristics within acceptable application parameters.

Substiute Parts

BZX79C22

onsemiIn Stock: 1161BZX79C22 Datasheet

Current PartRFQ

1N5251B

Microchip TechnologyIn Stock: 21681N5251B Datasheet

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1N5074

Microchip TechnologyIn Stock: 11431N5074 Datasheet

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BZX79-C22,113

NXP SemiconductorsIn Stock: 199479BZX79-C22,113 Datasheet

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BZX79-C22,133

NXP SemiconductorsIn Stock: 121015BZX79-C22,133 Datasheet

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BZX79-C22,143

NXP SemiconductorsIn Stock: 76148BZX79-C22,143 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the BZX79C22 is determined by the following critical parameters: nominal Zener voltage (22 V), voltage tolerance (±5%), maximum power dissipation capability, package type (through-hole axial), and operating temperature range. Parts are grouped into two categories:

Category 1: Direct Electrical Equivalents (500 mW Power Rating) Parts maintaining the 500 mW power specification with identical or superior electrical characteristics. These parts are suitable for direct replacement in applications where the original 500 mW rating is required.

Category 2: Higher Power Alternatives (3 W Power Rating) Parts with elevated power dissipation capability (3 W) while maintaining the 22 V nominal voltage and ±5% tolerance. These parts accommodate applications requiring increased thermal headroom or higher current handling.

All substitute parts maintain the 22 V nominal Zener voltage, ±5% tolerance, through-hole mounting configuration, and compatible package designations (DO-35, DO-204AH, or Axial).

Parameter Comparison

Engineering Selection Recommendations

Primary Equivalent (Active Status): The 1N5251B from Microchip Technology is the primary active equivalent, maintaining the 500 mW power rating and DO-35 package configuration. This part is suitable for direct replacement in applications where the original specifications are required. The 1N5251B exhibits lower impedance (29 Ohms versus 55 Ohms), providing improved voltage regulation characteristics. The operating temperature range is reduced to -65°C ~ 175°C compared to the original -65°C ~ 200°C specification.

Secondary Equivalents (Active Status, Reduced Power): The BZX79-C22,133, BZX79-C22,113, and BZX79-C22,143 from NXP Semiconductors are active alternatives with 400 mW power ratings. These parts maintain identical impedance (55 Ohms) and operating temperature range (-65°C ~ 200°C) to the original BZX79C22. The 100 mW power reduction requires verification that application current demands do not exceed the reduced thermal budget.

Higher Power Alternative (Active Status): The 1N5074 from Microchip Technology provides a 3 W power rating with significantly lower impedance (10 Ohms), suitable for applications requiring elevated power dissipation or improved voltage regulation. This part uses an Axial package configuration and operates within -65°C ~ 175°C temperature range.

All substitute parts maintain REACH compliance and EAR99 export classification consistent with the original component.

Frequently Asked Questions (FAQ)

Q: Can the 1N5251B directly replace the BZX79C22? A: The 1N5251B is functionally equivalent for applications operating within -65°C ~ 175°C. Both parts maintain 22 V nominal voltage, ±5% tolerance, 500 mW power rating, and DO-35 package configuration. The reduced impedance of the 1N5251B (29 Ohms) provides superior voltage regulation performance.

Q: What is the difference between the NXP BZX79-C22 variants (133, 113, 143)? A: The BZX79-C22,133, BZX79-C22,113, and BZX79-C22,143 are functionally identical with respect to electrical specifications. All three maintain 22 V nominal voltage, ±5% tolerance, 400 mW power rating, 55 Ohms impedance, and -65°C ~ 200°C operating temperature. The numeric suffixes denote packaging or manufacturing variants without electrical differentiation.

Q: Why would I select the 1N5074 over the 1N5251B? A: The 1N5074 is selected for applications requiring power dissipation exceeding 500 mW or where improved voltage regulation (10 Ohms impedance) is critical. The 3 W rating accommodates higher current applications. The Axial package may be preferred in specific PCB layouts. Operating temperature range is limited to -65°C ~ 175°C.

Q: Are the NXP BZX79-C22 parts suitable for the original BZX79C22 application? A: The NXP variants are suitable for applications where 400 mW power dissipation is sufficient. These parts maintain identical impedance (55 Ohms) and extended operating temperature range (-65°C ~ 200°C) matching the original specification. Applications requiring the full 500 mW rating require the 1N5251B or 1N5074.

Q: What package considerations apply to these substitutes? A: The 1N5251B, BZX79-C22,133, BZX79-C22,113, and BZX79-C22,143 are compatible with DO-35 package footprints. The 1N5074 uses an Axial package requiring different PCB layout accommodation. All parts are through-hole mounted components.

Q: Are there compliance or certification differences between these parts? A: All substitute parts maintain REACH compliance and EAR99 export classification. The 1N5251B is RoHS non-compliant. The BZX79-C22 variants from NXP maintain Moisture Sensitivity Level 1 (Unlimited) classification matching the original component.