ZPY91-TR Zener Diode 120V 1.3W Equivalent & Substitute Parts

Part Overview

The ZPY91-TR is a 120V Zener diode rated at 1.3W maximum power dissipation, manufactured by Vishay General Semiconductor - Diodes Division in DO-204AL (DO-41) axial through-hole package. This component is classified as obsolete, necessitating identification of active equivalent alternatives for ongoing design support and procurement. The part carries AEC-Q101 automotive qualification and ROHS3 compliance. Substitute parts must maintain electrical compatibility across voltage regulation, power handling, and thermal operating ranges while accommodating packaging and compliance requirements.

Substiute Parts

ZPY91-TR

Vishay General Semiconductor - Diodes DivisionIn Stock: 1161ZPY91-TR Datasheet

Current PartRFQ

1N5951BG

Microsemi CorporationIn Stock: 9371N5951BG Datasheet

MFR RecommendedRFQ

1N5951CG

Microsemi CorporationIn Stock: 8581N5951CG Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ZPY91-TR is determined by strict equivalence across the following electrical and mechanical parameters:

Primary Equivalence Criteria:

• Zener voltage: 120 V nominal
• Package type: DO-204AL (DO-41) axial through-hole
• Mounting configuration: Through-hole compatible with ZPY91-TR footprints

Secondary Compatibility Parameters:

• Power rating: Minimum 1.25 W (acceptable reduction from 1.3 W within thermal design margins)
• Voltage tolerance: ±2% to ±5% (tighter tolerance acceptable)
• Operating temperature range: Must support minimum 175°C upper limit
• Reverse leakage current: Specified at rated voltage conditions

The substitute parts 1N5951BG and 1N5951CG meet these criteria. Both are manufactured by Microsemi Corporation, maintain 120V nominal Zener voltage, utilize identical DO-204AL packaging, and support through-hole mounting. Power ratings of 1.25W are functionally equivalent for applications designed within ZPY91-TR thermal specifications. Voltage tolerance differences (±5% vs. ±2%) do not preclude substitution; tighter tolerance variants provide enhanced precision.

Parameter Comparison

Engineering Selection Recommendations

1N5951CG (Primary Substitute): The 1N5951CG is the preferred substitute for ZPY91-TR applications. This part maintains active product status, ensuring long-term availability and supply chain stability. The ±2% voltage tolerance provides superior regulation precision compared to the original ±5% specification. Operating temperature range (-65°C to 175°C) fully encompasses the ZPY91-TR maximum rating. DO-204AL packaging ensures direct mechanical and electrical compatibility. RoHS non-compliance status does not affect substitution validity; compliance requirements are application-dependent and determined by end-use regulations.

1N5951BG (Secondary Substitute): The 1N5951BG serves as an alternative when ±5% voltage tolerance is specifically required to match original specifications. This part is functionally equivalent to 1N5951CG with identical electrical performance except for tolerance rating. Active product status and identical packaging support seamless integration.

Compliance Considerations: Both substitute parts are RoHS non-compliant, whereas ZPY91-TR is ROHS3 compliant. Applications subject to RoHS directives must evaluate compliance requirements independently. Both substitutes maintain REACH unaffected status and EAR99 export classification, matching the original part.

Frequently Asked Questions (FAQ)

Q: Can 1N5951BG and 1N5951CG be used interchangeably with ZPY91-TR?

A: Yes. Both parts maintain 120V nominal Zener voltage, identical DO-204AL through-hole packaging, and equivalent operating temperature ranges. The 0.05W reduction in power rating (1.25W vs. 1.3W) is acceptable for designs operating within thermal margins of the original specification.

Q: What is the difference between 1N5951BG and 1N5951CG?

A: The primary difference is voltage tolerance: 1N5951BG specifies ±5% tolerance, matching ZPY91-TR; 1N5951CG specifies ±2% tolerance, providing tighter regulation. Both parts are electrically and mechanically identical otherwise. Selection depends on circuit tolerance requirements.

Q: Why do the substitute parts show higher impedance (380 Ohms vs. 120 Ohms)?

A: Impedance variation reflects manufacturing differences between Vishay and Microsemi designs. Both values fall within acceptable ranges for 120V Zener diodes and do not preclude substitution. Circuit performance is determined by application-specific impedance requirements, not impedance alone.

Q: Are there RoHS compliance implications for using 1N5951BG or 1N5951CG?

A: Both substitutes are RoHS non-compliant, whereas ZPY91-TR is ROHS3 compliant. Applications subject to RoHS directives (EU 2011/65/EU or equivalent) must verify compliance requirements with procurement and regulatory teams. Substitution is technically valid; compliance determination is application-specific.

Q: What is the reverse leakage current difference, and does it affect substitution?

A: ZPY91-TR specifies 500 nA @ 68V; substitutes specify 1 µA @ 91.2V. The higher leakage in substitutes is measured at a higher voltage reference point. Both values are within acceptable ranges for 120V Zener applications and do not preclude substitution for standard voltage regulation circuits.

Q: Can these parts be used in automotive applications?

A: ZPY91-TR carries AEC-Q101 automotive qualification. Substitute parts do not list AEC-Q101 certification. Automotive applications requiring AEC-Q101 qualification must verify alternative qualified sources or obtain qualification documentation from Microsemi before substitution.