BST39-QX Equivalent & Substitute Parts

Part Overview

The BST39-QX is an NPN bipolar junction transistor manufactured by Nexperia USA Inc., designed for high-voltage switching and amplification applications. This Surface Mount device operates at 350 V collector-emitter breakdown voltage with a maximum collector current of 100 mA and power dissipation of 1.3 W. The part is classified as Active product status and carries automotive-grade qualification under AEC-Q101 standard, making it suitable for demanding automotive and industrial applications. Substitute parts are identified based on matching electrical characteristics, mechanical compatibility, and compliance certifications to ensure direct functional replacement without circuit redesign.

Substiute Parts

BST39-QX

Nexperia USA Inc.In Stock: 931BST39-QX Datasheet

Current PartRFQ

BST39,115

Nexperia USA Inc.In Stock: 828BST39,115 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the BST39-QX are identified through strict parametric matching across electrical and mechanical specifications. The substitution logic is based on the following critical parameters that must remain constant:

Electrical Parameters (Must Match):

• Transistor Type: NPN
• Collector Current (Ic) Maximum: 100 mA
• Collector-Emitter Breakdown Voltage: 350 V
• Vce Saturation: 500 mV @ 4 mA, 50 mA
• Collector Cutoff Current (ICBO): 20 nA
• DC Current Gain (hFE) Minimum: 40 @ 20 mA, 10 V
• Power Dissipation Maximum: 1.3 W
• Transition Frequency: 70 MHz
• Operating Temperature Maximum: 150°C

Mechanical Parameters (Must Match):

• Mounting Type: Surface Mount
• Package / Case: TO-243AA
• Supplier Device Package: SOT-89

Compliance Parameters (Must Match):

• Grade: Automotive
• Qualification: AEC-Q101
• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity Level: 1 (Unlimited)

Parts meeting all these criteria are classified as parametric equivalents and direct substitutes. Packaging format variations (Tape & Reel versus Cut Tape) do not affect electrical or mechanical compatibility and are considered acceptable substitution options.

Parameter Comparison

Engineering Selection Recommendations

The BST39,115 is a direct parametric equivalent to the BST39-QX. Both parts are manufactured by Nexperia USA Inc. and share identical electrical characteristics, mechanical specifications, and compliance certifications. The only difference between these parts is the packaging format: BST39-QX is supplied in Tape & Reel format, while BST39,115 is available in Cut Tape and Digi-Reel format.

Selection Criteria:

1. Electrical Compatibility: All electrical parameters are identical. The BST39,115 can be substituted in any circuit designed for the BST39-QX without modification.

2. Mechanical Compatibility: Both parts use the same TO-243AA package and SOT-89 supplier device package, ensuring identical PCB footprint and assembly compatibility.

3. Compliance and Certification: Both parts carry automotive-grade qualification (AEC-Q101) and ROHS3 compliance, meeting the same regulatory and environmental standards.

4. Product Status: Both parts maintain Active product status, ensuring continued availability and manufacturer support.

5. Packaging Consideration: Selection between BST39-QX and BST39,115 should be based on supply chain requirements and assembly process compatibility. Tape & Reel format is typically preferred for high-volume automated assembly, while Cut Tape format offers flexibility for lower-volume or mixed-component operations.

Frequently Asked Questions (FAQ)

Q: Can BST39,115 be used as a direct replacement for BST39-QX in production?

A: Yes. The BST39,115 is a parametric equivalent with identical electrical and mechanical specifications. No circuit redesign or PCB modification is required. The only consideration is packaging format compatibility with your assembly process.

Q: Are there any electrical performance differences between BST39-QX and BST39,115?

A: No. Both parts have identical electrical characteristics including collector current, breakdown voltage, saturation voltage, current gain, power dissipation, and transition frequency. They perform identically in circuit applications.

Q: Do both parts meet automotive qualification requirements?

A: Yes. Both BST39-QX and BST39,115 carry AEC-Q101 automotive qualification and are classified as Automotive grade. Both are ROHS3 compliant and have unlimited moisture sensitivity level (MSL 1).

Q: What is the difference between Tape & Reel and Cut Tape packaging?

A: Tape & Reel (TR) format supplies components on continuous carrier tape wound on reels, optimized for high-speed automated pick-and-place assembly. Cut Tape (CT) format supplies components on cut segments of carrier tape, suitable for lower-volume assembly or manual handling. Both formats contain identical components with the same electrical and mechanical properties.

Q: Can I mix BST39-QX and BST39,115 in the same production batch?

A: Yes. Since both parts are parametric equivalents with identical specifications and certifications, they can be used interchangeably in the same circuit design and production batch without affecting performance or reliability.

Q: What is the base product number for these parts?

A: The base product number is BST39. Both BST39-QX and BST39,115 are variants of this base product, differentiated by packaging format and supplier designation.