BST39,115 Equivalent & Substitute Parts

Part Overview

The BST39,115 is an NPN bipolar junction transistor manufactured by Nexperia USA Inc., rated for 350 V collector-emitter breakdown voltage and 100 mA maximum collector current in a surface mount SOT-89 package. This device is classified as Active product status with AEC-Q101 automotive qualification and ROHS3 compliance. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are required due to component availability, supply chain considerations, or design flexibility within specified parameter ranges.

Key Parameters

Parameter	Value	Unit
Transistor Type	NPN	—
Voltage - Collector Emitter Breakdown (Max)	350	V
Current - Collector (Ic) (Max)	100	mA
Power - Max	1.3	W
Frequency - Transition	70	MHz
Vce Saturation (Max) @ Ib, Ic	500mV @ 4mA, 50mA	—
DC Current Gain (hFE) (Min) @ Ic, Vce	40 @ 20mA, 10V	—
Mounting Type	Surface Mount	—
Package / Case	TO-243AA	—
Supplier Device Package	SOT-89	—
Operating Temperature (Max)	150	°C
RoHS Status	ROHS3 Compliant	—

Substitute Part Grouping Explanation

Substitution of NPN bipolar junction transistors is determined by electrical parameter compatibility within the following criteria:

Primary Compatibility Parameters:

Transistor type (NPN)
Voltage rating (Collector-Emitter Breakdown): substitute must equal or exceed the main part specification
Current rating (Ic Max): substitute must equal or exceed the main part specification
Power dissipation (P Max): substitute must equal or exceed the main part specification
Frequency response (Transition Frequency): substitute must equal or exceed the main part specification
DC current gain (hFE): substitute must meet or exceed minimum specification
Vce saturation characteristics: substitute must be compatible with application requirements
Mechanical compatibility: package type (TO-243AA / SOT-89) and mounting type (Surface Mount)
Compliance: RoHS3 status and operating temperature range

Substitution Logic: Parts BST39TA, DXTA42-13, and SXTA42TA are grouped as substitutes based on shared mechanical packaging (TO-243AA / SOT-89-3 surface mount), NPN transistor type, and overlapping electrical specifications. BST39TA maintains the 350 V rating of the main part with enhanced current capability (500 mA). DXTA42-13 and SXTA42TA operate at 300 V with 500 mA current rating, representing a lower voltage specification suitable for applications not requiring the full 350 V rating.

Parameter Comparison

Parameter	BST39,115 (Main)	BST39TA	DXTA42-13	SXTA42TA
Manufacturer	Nexperia USA Inc.	Diodes Incorporated	Diodes Incorporated	Diodes Incorporated
Transistor Type	NPN	NPN	NPN	NPN
Voltage - Collector Emitter Breakdown (Max)	350 V	350 V	300 V	300 V
Current - Collector (Ic) (Max)	100 mA	500 mA	500 mA	500 mA
Power - Max	1.3 W	1 W	1 W	1 W
Frequency - Transition	70 MHz	70 MHz	50 MHz	50 MHz
Vce Saturation (Max) @ Ib, Ic	500mV @ 4mA, 50mA	500mV @ 4mA, 50mA	500mV @ 2mA, 20mA	500mV @ 2mA, 20mA
DC Current Gain (hFE) (Min) @ Ic, Vce	40 @ 20mA, 10V	40 @ 20mA, 10V	40 @ 30mA, 10V	40 @ 30mA, 10V
Current - Collector Cutoff (Max)	20 nA	20 nA	100 nA	100 nA
Package / Case	TO-243AA	TO-243AA	TO-243AA	TO-243AA
Supplier Device Package	SOT-89	SOT-89-3	SOT-89-3	SOT-89-3
Operating Temperature (Max)	150°C	150°C	150°C	150°C
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant
Packaging Type	Cut Tape (CT) & Digi-Reel®	Tape & Reel (TR)	Tape & Reel (TR)	Tape & Reel (TR)

Engineering Selection Recommendations

BST39TA (Diodes Incorporated): BST39TA is the closest electrical equivalent to BST39,115, maintaining the 350 V collector-emitter breakdown voltage and 70 MHz transition frequency. This substitute provides enhanced current handling capability (500 mA vs. 100 mA) while preserving voltage and frequency specifications. Both devices share identical Vce saturation and DC current gain characteristics at specified test conditions. BST39TA is ROHS3 compliant and rated to 150°C maximum junction temperature. Selection of BST39TA is appropriate when higher current capacity is beneficial or when Nexperia supply is constrained.

DXTA42-13 (Diodes Incorporated): DXTA42-13 operates at 300 V collector-emitter breakdown voltage, representing a 50 V reduction from the main part specification. This substitute is suitable for applications where the full 350 V rating is not required. DXTA42-13 provides 500 mA current capability and 1 W power dissipation. Transition frequency is 50 MHz, lower than the main part. DXTA42-13 is ROHS3 compliant and rated to 150°C maximum junction temperature.

SXTA42TA (Diodes Incorporated): SXTA42TA shares electrical specifications with DXTA42-13 (300 V, 500 mA, 50 MHz, 1 W) and is suitable for identical application requirements. SXTA42TA extends the operating temperature range to −65°C minimum, providing enhanced low-temperature performance compared to the main part. SXTA42TA is ROHS3 compliant. Selection of SXTA42TA is appropriate when extended low-temperature operation is required.

All substitute parts maintain TO-243AA mechanical compatibility and surface mount mounting type. All devices are Active product status with ROHS3 compliance and REACH unaffected status.

Frequently Asked Questions (FAQ)

Q: Can BST39TA directly replace BST39,115 in all applications?

A: BST39TA is electrically compatible with BST39,115 for applications operating within the specified parameter ranges. Both devices share 350 V voltage rating, 70 MHz transition frequency, and identical Vce saturation and DC current gain characteristics. BST39TA provides higher current capability (500 mA vs. 100 mA), which is a superset of the main part specification. Mechanical compatibility is confirmed through identical TO-243AA package and surface mount mounting type. Packaging format differs (Tape & Reel vs. Cut Tape & Digi-Reel), which may affect procurement and assembly processes.

Q: What is the voltage difference between BST39,115 and DXTA42-13?

A: BST39,115 is rated for 350 V maximum collector-emitter breakdown voltage, while DXTA42-13 is rated for 300 V. The 50 V difference means DXTA42-13 is suitable only for applications where the maximum voltage stress does not exceed 300 V. Applications requiring the full 350 V rating must use BST39,115 or BST39TA.

Q: Are DXTA42-13 and SXTA42TA interchangeable?

A: DXTA42-13 and SXTA42TA share identical electrical specifications (300 V, 500 mA, 50 MHz, 1 W) and mechanical packaging (TO-243AA, SOT-89-3, surface mount). The primary difference is operating temperature range: DXTA42-13 operates from −55°C to 150°C, while SXTA42TA operates from −65°C to 150°C. Selection between these parts depends on low-temperature performance requirements. Both are ROHS3 compliant and suitable for identical mechanical applications.

Q: What is the significance of the transition frequency difference between BST39,115 and DXTA42-13?

A: BST39,115 has a transition frequency (fT) of 70 MHz, while DXTA42-13 has 50 MHz. Transition frequency indicates the frequency at which current gain drops to unity. Applications requiring operation at frequencies approaching or exceeding 50 MHz should use BST39,115 or BST39TA (both 70 MHz) to ensure adequate gain at the operating frequency.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. BST39,115, BST39TA, DXTA42-13, and SXTA42TA are all ROHS3 compliant and REACH unaffected. All devices are suitable for applications with RoHS3 compliance requirements.

Q: What packaging format differences exist between the main part and substitutes?

A: BST39,115 is supplied in Cut Tape (CT) and Digi-Reel® packaging formats. BST39TA, DXTA42-13, and SXTA42TA are supplied in Tape & Reel (TR) format. All devices use identical TO-243AA mechanical package and SOT-89 / SOT-89-3 supplier device packages suitable for surface mount assembly. Packaging format selection affects procurement, storage, and automated assembly processes but does not affect electrical or mechanical compatibility.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message