ZPY43-TAP Zener Diode Equivalent & Substitute Parts

Part Overview

The ZPY43-TAP is a 43V 1.3W Zener diode manufactured by Vishay General Semiconductor - Diodes Division, housed in a DO-41 axial through-hole package. This component is classified as Active product status and carries AEC-Q101 automotive qualification. Substitute parts become necessary when the primary part experiences supply constraints, extended lead times, or inventory limitations. The ZPY43-TAP maintains ROHS3 compliance and operates across an extended temperature range up to 175°C, making it suitable for automotive and industrial applications requiring voltage regulation and transient protection.

Substiute Parts

ZPY43-TAP

Vishay General Semiconductor - Diodes DivisionIn Stock: 914ZPY43-TAP Datasheet

Current PartRFQ

1N4755A

Lumimax Optoelectronic TechnologyIn Stock: 43431N4755A Datasheet

MFR RecommendedRFQ

1N4755A-T50A

Fairchild SemiconductorIn Stock: 337521N4755A-T50A Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the ZPY43-TAP is determined by the following critical parameters:

Primary Matching Criteria:

• Voltage - Zener (Nom): 43V (exact match required)
• Tolerance: ±5% (exact match required)
• Package / Case: DO-204AL, DO-41, Axial (mechanical compatibility)
• Mounting Type: Through Hole (circuit board integration requirement)

Secondary Compatibility Factors:

• Power - Max: Substitute must equal or exceed 1.3W
• Impedance (Max): Lower impedance values are acceptable
• Current - Reverse Leakage: Lower leakage values are acceptable
• Operating Temperature Range: Must support application requirements

The substitute parts 1N4755A and 1N4755A-T50A both satisfy the primary matching criteria with identical zener voltage (43V) and tolerance (±5%). Both are housed in DO-41 axial through-hole packages. However, both substitute parts specify 1W maximum power dissipation, which is lower than the ZPY43-TAP specification of 1.3W. This represents a functional limitation in thermal handling capacity.

Parameter Comparison

Engineering Selection Recommendations

ZPY43-TAP (Primary Component): The ZPY43-TAP maintains Active product status with AEC-Q101 automotive qualification, making it the preferred selection for automotive and mission-critical applications. Its 1.3W power rating provides superior thermal margin compared to substitute options. ROHS3 compliance ensures regulatory alignment with current environmental standards.

1N4755A-T50A (Fairchild Semiconductor): This substitute demonstrates Active product status with 33,728 units in stock, providing supply security. The part meets the core electrical specifications (43V, ±5% tolerance) and maintains DO-41 axial through-hole compatibility. However, the 1W power rating represents a 23% reduction in thermal capacity relative to the ZPY43-TAP. The 70 Ohm impedance specification is double that of the main part. This substitute is suitable for applications where thermal dissipation does not approach the 1.3W limit.

1N4755A (Lumimax Optoelectronic Technology): This substitute also maintains Active product status with 4,280 units available. Electrical specifications match the Fairchild variant (43V, ±5%, 1W, 70 Ohms). Operating temperature range extends to 200°C, exceeding the ZPY43-TAP specification. Selection of this part should be based on supply availability and application thermal requirements.

Compliance Considerations: The ZPY43-TAP carries explicit AEC-Q101 qualification, which is absent from both substitute parts. Applications requiring automotive qualification should prioritize the ZPY43-TAP. The substitute parts do not specify automotive grade designation.

Frequently Asked Questions (FAQ)

Q: Can 1N4755A or 1N4755A-T50A directly replace ZPY43-TAP in all applications?

A: Direct replacement is limited by power dissipation capacity. Both substitutes are rated at 1W maximum power, compared to the ZPY43-TAP specification of 1.3W. Substitution is valid only when circuit design ensures power dissipation remains below 1W. Applications operating near or above 1W dissipation require the ZPY43-TAP.

Q: What are the impedance differences, and do they affect circuit performance?

A: The ZPY43-TAP specifies 35 Ohms maximum impedance, while both substitutes specify 70 Ohms. Higher impedance results in increased voltage ripple and slower transient response. Applications requiring low-impedance voltage regulation should use the ZPY43-TAP. General-purpose voltage clamping applications tolerate the higher impedance of substitute parts.

Q: Are the substitute parts suitable for automotive applications?

A: The ZPY43-TAP carries AEC-Q101 automotive qualification. The substitute parts (1N4755A and 1N4755A-T50A) do not specify automotive grade or qualification. Automotive applications requiring compliance with AEC-Q101 standards must use the ZPY43-TAP.

Q: How do reverse leakage specifications compare?

A: The ZPY43-TAP specifies 500 nanoamperes reverse leakage at 32V. Both substitutes specify 5 microamperes at 32.7V, representing a 10-fold increase in leakage current. Applications sensitive to leakage current (precision voltage references, high-impedance circuits) should prioritize the ZPY43-TAP.

Q: Are all three parts mechanically compatible in the same circuit board layout?

A: Yes. All three parts use DO-41 axial through-hole packaging with identical mechanical dimensions. PCB footprints and lead spacing are compatible across ZPY43-TAP, 1N4755A, and 1N4755A-T50A.

Q: What is the temperature operating range difference?

A: The ZPY43-TAP operates to 175°C maximum. Both substitutes extend to 200°C. For applications operating below 175°C, both substitutes provide additional thermal margin. Applications requiring operation above 175°C cannot use the ZPY43-TAP.

Q: Which substitute offers better supply availability?

A: The 1N4755A-T50A (Fairchild Semiconductor) shows 33,728 units in stock, providing superior supply security compared to 1N4755A (4,280 units) and ZPY43-TAP (816 units).