BU508A Equivalent & Substitute Parts

Part Overview

The BU508A is an NPN bipolar junction transistor manufactured by STMicroelectronics, rated for 700 V collector-emitter breakdown voltage and 8 A maximum collector current. This device is packaged in TO-247-3 through-hole configuration and is rated for 125 W maximum power dissipation. The BU508A is classified as obsolete, making identification of suitable substitute components necessary for ongoing design support and production continuity. Active equivalent parts maintain identical electrical and mechanical specifications while offering current manufacturing availability.

Substiute Parts

BU508A

STMicroelectronicsIn Stock: 2234BU508A Datasheet

Current PartRFQ

BU508AW

STMicroelectronicsIn Stock: 15866BU508AW Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BU508A is determined by strict equivalence across the following critical parameters:

Electrical Specifications:

• Transistor type classification (NPN)
• Maximum collector-emitter breakdown voltage (700 V)
• Maximum collector current rating (8 A)
• Maximum power dissipation (125 W)
• Operating temperature range (150°C TJ maximum)

Mechanical Specifications:

• Package type (TO-247-3)
• Mounting configuration (Through Hole)

Compliance & Regulatory:

• RoHS3 compliance status
• REACH status classification

The BU508AW qualifies as a direct substitute based on identical ratings across all critical electrical and mechanical parameters. Both devices share the same base product number (BU508) and maintain equivalent performance boundaries within the specified operating envelope.

Parameter Comparison

Engineering Selection Recommendations

The BU508AW is the direct substitute for the obsolete BU508A. Both devices maintain identical electrical performance specifications and mechanical packaging, ensuring functional equivalence in circuit applications. The BU508AW carries active product status with current manufacturing availability, providing supply continuity for designs currently utilizing the BU508A.

Both parts satisfy ROHS3 compliance requirements and REACH regulatory status, supporting deployment in regulated markets without additional qualification. The transition from BU508A to BU508AW requires no circuit redesign or thermal management modifications, as all critical performance parameters remain unchanged.

Frequently Asked Questions (FAQ)

Q: Can the BU508AW directly replace the BU508A in existing designs?

A: Yes. The BU508AW maintains identical electrical ratings (700 V breakdown, 8 A collector current, 125 W power dissipation) and mechanical packaging (TO-247-3 through-hole). No circuit modifications are required.

Q: What is the primary difference between BU508A and BU508AW?

A: The BU508A is classified as obsolete, while the BU508AW is active production. The BU508AW offers current manufacturing availability and supply continuity. Electrical and mechanical specifications are equivalent.

Q: Are there packaging differences between these parts?

A: Both devices use TO-247-3 through-hole packaging. The BU508A is supplied in standard packaging, while the BU508AW is supplied in tube packaging. Pin configuration and thermal characteristics remain identical.

Q: Do both parts meet the same regulatory compliance standards?

A: Yes. Both the BU508A and BU508AW are ROHS3 compliant and REACH unaffected, supporting equivalent regulatory deployment.

Q: What parameters must remain constant for substitution validity?

A: Substitution validity depends on maintaining identical transistor type (NPN), collector-emitter breakdown voltage (700 V), maximum collector current (8 A), power rating (125 W), package type (TO-247-3), and mounting configuration (through-hole).