1N459 Equivalent & Substitute Parts

Part Overview

The 1N459 is a general-purpose rectifier diode manufactured by onsemi, rated for 200 V DC reverse voltage and 500 mA average rectified current in a DO-35 through-hole package. This part is classified as obsolete, necessitating identification of equivalent and substitute components for ongoing design support and procurement continuity. Equivalent parts maintain identical electrical and mechanical specifications, while substitute parts provide functional alternatives with modified parameters within acceptable application ranges.

Substiute Parts

1N459

onsemiIn Stock: 6971N459 Datasheet

Current PartRFQ

1N459ATR

Fairchild SemiconductorIn Stock: 161491N459ATR Datasheet

DirectRFQ

1N459A

Microchip TechnologyIn Stock: 8361N459A Datasheet

Parametric EquivalentRFQ

1N645-1

Solid State Inc.In Stock: 687041N645-1 Datasheet

SimilarRFQ

1N459-T50R

Fairchild SemiconductorIn Stock: 611371N459-T50R Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts are classified into two categories based on electrical parameter alignment with the 1N459:

Direct Equivalent (Identical Electrical Specifications): Parts maintaining all critical electrical parameters—200 V reverse voltage, 500 mA average rectified current, 1 V forward voltage at 100 mA, standard recovery speed, 25 nA reverse leakage at 175 V, and 6 pF capacitance—are classified as direct equivalents. These parts support drop-in replacement without circuit redesign.

Parametric Equivalent (Modified Current Rating): Parts with identical voltage ratings and recovery characteristics but reduced average rectified current (150 mA instead of 500 mA) are classified as parametric equivalents. These parts are suitable for applications where the circuit current requirement does not exceed the substitute part's rating.

Similar (Modified Voltage and Current Ratings): Parts with increased reverse voltage (225 V) and reduced average rectified current (400 mA) are classified as similar alternatives. These parts accommodate applications requiring higher voltage margins while accepting reduced current capacity.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Active Status Required): The 1N459ATR manufactured by Fairchild Semiconductor is the recommended direct equivalent. This part maintains identical electrical specifications and is currently in active production status, ensuring long-term availability and supply chain stability. The 1N459-T50R, while electrically equivalent, carries obsolete status and should not be selected for new designs.

For Current-Limited Applications: The 1N459A manufactured by Microchip Technology is suitable for applications where circuit current requirements do not exceed 150 mA. This part is in active production status. Note that the operating temperature range is reduced to −65°C to 150°C (versus 175°C maximum junction temperature of the main part), and reverse leakage increases to 1 µA at 200 V. RoHS non-compliance status must be evaluated against design requirements.

For Voltage-Margin Applications: The 1N645-1 manufactured by Solid State Inc. provides 225 V reverse voltage rating with 400 mA average rectified current. This part is in active production status and carries RoHS3 compliance certification. Selection is appropriate for applications requiring higher voltage headroom with reduced current capacity. Forward voltage specification differs (1 V @ 400 mA versus 1 V @ 100 mA), requiring circuit analysis for voltage drop impact.

Frequently Asked Questions (FAQ)

Q: Can the 1N459ATR be used as a direct replacement for the 1N459?

A: Yes. The 1N459ATR maintains identical electrical specifications across all critical parameters: 200 V reverse voltage, 500 mA average rectified current, 1 V forward voltage at 100 mA, standard recovery speed, 25 nA reverse leakage, and 6 pF capacitance. Both parts use the DO-35 package. The 1N459ATR is in active production status, making it the preferred replacement for obsolete 1N459 designs.

Q: What is the difference between the 1N459A and the 1N459?

A: The 1N459A differs in two critical parameters: average rectified current is reduced to 150 mA (versus 500 mA), and maximum junction temperature is 150°C (versus 175°C). The 1N459A is classified as a parametric equivalent suitable only for applications where circuit current does not exceed 150 mA. Reverse leakage also increases to 1 µA at 200 V. The 1N459A is in active production status.

Q: When should the 1N645-1 be selected over the 1N459ATR?

A: The 1N645-1 should be selected when the application requires reverse voltage margin beyond 200 V. The 1N645-1 provides 225 V reverse voltage rating. However, average rectified current is reduced to 400 mA, and reverse leakage increases to 50 nA at 225 V. Circuit analysis is required to confirm that 400 mA current capacity is sufficient and that the increased leakage does not impact circuit performance.

Q: Are all substitute parts available in the same DO-35 package?

A: Yes. All listed substitute parts—1N459ATR, 1N459A, 1N645-1, and 1N459-T50R—are available in the DO-35 through-hole package (DO-204AH designation). Package compatibility is confirmed across all alternatives.

Q: What is the product status significance for part selection?

A: Product status indicates manufacturing and supply availability. Active status parts (1N459ATR, 1N459A, 1N645-1) are in current production and recommended for new designs. Obsolete status parts (1N459, 1N459-T50R) should not be selected for new designs due to uncertain long-term availability, though they may be acceptable for legacy system maintenance where existing inventory is available.

Q: Does the 1N459A meet RoHS compliance requirements?

A: The 1N459A is marked as RoHS non-compliant. If RoHS compliance is required for the application, the 1N459ATR or 1N645-1 must be evaluated for their respective compliance status. The 1N645-1 carries RoHS3 compliance certification.