Equivalent & Substitute Parts for 6A8 General Purpose Rectifier Diode

Part Overview

The 6A8 is a general purpose rectifier diode manufactured by Micro Commercial Co, rated for 800 V DC reverse voltage and 6 A average rectified current in an R-6 axial through-hole package. This component is classified as obsolete, indicating it is no longer in active production. Locating equivalent and substitute parts is necessary to support ongoing maintenance, repair, and legacy system requirements where this diode specification remains applicable.

Substiute Parts

6A8

Micro Commercial CoIn Stock: 8926A8 Datasheet

Current PartRFQ

6A8-TP

Micro Commercial CoIn Stock: 50476A8-TP Datasheet

DirectRFQ

1N5553

Solid State Inc.In Stock: 10091N5553 Datasheet

SimilarRFQ

1N5554

Solid State Inc.In Stock: 12181N5554 Datasheet

SimilarRFQ

GI758-E3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 8371GI758-E3/54 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the 6A8 rectifier diode is determined by electrical and mechanical compatibility across the following critical parameters:

Voltage Rating (Vr): The substitute part must support a minimum DC reverse voltage of 800 V. Parts with equal or higher voltage ratings are acceptable.

Current Rating (Io): The substitute part must support a minimum average rectified current of 6 A. Parts with equal or higher current ratings are acceptable.

Forward Voltage (Vf): The substitute part must not exceed 950 mV at the rated current to maintain circuit performance and thermal characteristics.

Recovery Speed: The substitute part must operate at standard recovery speed (>500 ns, >200 mA) to ensure compatibility with circuit timing requirements.

Reverse Leakage Current: The substitute part must maintain reverse leakage current at or below 10 µA at 800 V to preserve circuit reliability.

Mounting Type and Package: The substitute part must be through-hole mounted in an axial configuration to ensure mechanical compatibility with existing PCB layouts and assembly processes.

Substitute parts are grouped into two categories: direct equivalents (identical electrical and mechanical specifications) and similar parts (meeting or exceeding all critical electrical parameters with compatible packaging).

Parameter Comparison

Engineering Selection Recommendations

Direct Equivalent (Preferred for Legacy Support):

The 6A8-TP is the direct equivalent to the 6A8, manufactured by Micro Commercial Co with identical electrical specifications (800 V, 6 A, 950 mV forward voltage). The 6A8-TP differs only in packaging format (Cut Tape versus bulk) and product status (Not For New Designs). This part maintains full compatibility with existing designs and provides the highest level of functional equivalence. The 6A8-TP carries ROHS3 compliance, offering improved environmental and regulatory alignment compared to the non-compliant 6A8.

Full-Specification Equivalent (Active Production):

The GI758-E3/54 manufactured by Vishay General Semiconductor meets all electrical requirements of the 6A8 with identical voltage (800 V), current (6 A), and forward voltage (950 mV @ 6 A) specifications. This part is in active production status, ensuring long-term availability. The GI758-E3/54 operates within a wider temperature range (-50°C ~ 150°C) and exhibits lower reverse leakage current (5 µA versus 10 µA). The package designation (P600 versus R-6) requires physical verification for PCB footprint compatibility, though both are axial through-hole configurations.

Current-Limited Alternatives (Derating Required):

The 1N5553 and 1N5554 manufactured by Solid State Inc. are active production parts with full ROHS3 compliance. Both parts support the 800 V voltage requirement but are rated for only 3 A average rectified current, compared to the 6 A requirement of the 6A8. These parts are suitable only for applications where circuit current demand does not exceed 3 A. The 1N5554 provides higher voltage margin (1000 V rating) and both offer extended temperature ranges (-65°C ~ 200°C) and superior reverse leakage characteristics (1 µA).

Compliance Considerations:

All substitute parts listed carry ROHS3 compliance, addressing environmental and regulatory requirements not met by the obsolete 6A8. Selection should prioritize active production status (1N5553, 1N5554, GI758-E3/54) for new procurement to ensure supply chain continuity and regulatory alignment.

Frequently Asked Questions (FAQ)

Q: Can the 1N5553 or 1N5554 be used as a direct replacement for the 6A8?

A: The 1N5553 and 1N5554 are not direct replacements due to current rating limitations. Both parts are rated for 3 A average rectified current, while the 6A8 requires 6 A capacity. These parts are suitable only for applications where actual circuit current does not exceed 3 A. Voltage and forward voltage specifications are compatible, but current derating must be verified against circuit requirements.

Q: What is the difference between the 6A8 and 6A8-TP?

A: The 6A8 and 6A8-TP are electrically identical, both manufactured by Micro Commercial Co with 800 V, 6 A, and 950 mV specifications. The primary difference is packaging format: the 6A8 is supplied in bulk packaging, while the 6A8-TP is supplied in cut tape format. The 6A8-TP also carries ROHS3 compliance, whereas the 6A8 is non-compliant. Both parts are compatible with identical PCB layouts and assembly processes.

Q: Is the GI758-E3/54 compatible with the 6A8 in terms of physical package?

A: Both the 6A8 and GI758-E3/54 are axial through-hole diodes. The 6A8 uses an R-6 package designation, while the GI758-E3/54 uses a P600 designation. Physical dimensions and lead spacing must be verified against the specific PCB footprint to confirm mechanical compatibility, though both are standard axial configurations suitable for through-hole assembly.

Q: Why should I choose an active production part over the 6A8-TP?

A: Active production parts (1N5553, 1N5554, GI758-E3/54) offer long-term supply chain security and regulatory compliance. The 6A8-TP is marked "Not For New Designs," indicating limited future availability. For new procurement or long-term support, active production alternatives ensure sustained component availability and alignment with current environmental standards.

Q: What are the key electrical parameters that determine substitution compatibility?

A: Substitution compatibility is determined by five critical parameters: (1) DC reverse voltage rating must equal or exceed 800 V, (2) average rectified current rating must equal or exceed 6 A, (3) forward voltage must not exceed 950 mV at rated current, (4) recovery speed must meet standard specifications (>500 ns, >200 mA), and (5) reverse leakage current must not exceed 10 µA at 800 V. All substitute parts listed meet these criteria.

Q: Can I use a higher voltage-rated diode as a substitute?

A: Yes. The 1N5554 is rated for 1000 V, exceeding the 6A8 requirement of 800 V. Higher voltage ratings provide additional safety margin and are electrically compatible. However, the 1N5554 is limited to 3 A current, which may not meet circuit requirements. Voltage derating is not a concern; current derating must be evaluated against actual circuit demands.

Q: What is the significance of RoHS compliance in selecting a substitute?

A: RoHS compliance indicates the part meets environmental and regulatory standards for hazardous substance restrictions. The 6A8 is non-compliant, while all listed substitutes (6A8-TP, 1N5553, 1N5554, GI758-E3/54) carry ROHS3 compliance. For applications subject to environmental regulations or customer requirements, RoHS-compliant parts are necessary. For legacy system maintenance where regulatory requirements do not apply, non-compliant parts remain functional.