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Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

STMicroelectronics BD139-16

Name: BD139-16
Brand: STMicroelectronics
SKU: BD139-16
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BD139-16

Manufacturer:: STMicroelectronics

Category:: Single Bipolar Transistors

Package:: TO-225AA, TO-126-3

Datasheet:: BD139-16.pdf

Description:: TRANS NPN 80V 1.5A SOT-32-3

Quantity:: RFQ Add To RFQ list

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Inventory:6,727

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Product details

Overview

BD139-16 from STMicroelectronics is an NPN epitaxial planar bipolar junction transistor in SOT-32 package, designed for audio amplifier output stages and quasi-complementary driver circuits. It delivers 1.5 A continuous collector current, 80 V collector-emitter sustaining voltage (V_CEO(sus)), and DC current gain (h_FE) of 100–160 at I_C = 150 mA, enabling robust low-voltage power amplification in consumer audio systems.

For engineers reviewing the BD139-16 datasheet, BD139-16 pinout, BD139-16 application, or BD139-16 equivalent, key selection criteria include verified h_FE grouping (100–160), thermal resistance (R_thj-case = 10 °C/W), safe operating area under pulsed conditions, and compatibility with complementary PNP BD140-16 in push-pull configurations.

Technical Context

This transistor operates as a linear medium-power NPN switch or amplifier with fixed-base biasing capability. Its design emphasizes stable DC current gain across I_C = 5–500 mA and V_CE = 2 V, supported by low V_CE(sat) (0.5 V @ I_C = 0.5 A, I_B = 0.05 A) and controlled leakage (I_CBO ≤ 0.1 µA @ V_CB = 30 V, T_C = 25 °C).

The device uses epitaxial planar construction for consistent gain matching and thermal stability up to T_j = 150 °C. Its SOT-32 package enables direct mounting on heatsinks via case contact, leveraging R_thj-case = 10 °C/W for efficient power dissipation up to 12.5 W at T_C ≤ 25 °C.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO(sus)	80 V - Sustains 80 V collector-emitter voltage at I_C = 30 mA with zero base drive, defining safe linear operation limit
I_C (continuous)	1.5 A - Maximum DC collector current before thermal runaway or secondary breakdown
h_FE group	100–160 - Pre-selected DC current gain range at I_C = 150 mA, V_CE = 2 V for matched pair use
V_CE(sat)	0.5 V - Collector-emitter saturation voltage at I_C = 0.5 A, I_B = 0.05 A, minimizing conduction loss
R_thj-case	10 °C/W - Junction-to-case thermal resistance enables 12.5 W dissipation with 125 °C ΔT at case
P_TOT (T_C ≤ 25 °C)	12.5 W - Total power dissipation limit when case temperature held at or below 25 °C

Pinout & Package

SOT-32 (TO-126-compatible) plastic package with collector-connected tab for heatsink mounting; leads are emitter (1), base (2), collector (3) - pin 3 electrically connected to metal tab.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current exit path for NPN operation	Low-impedance terminal referenced to ground in common-emitter amplifier configurations
2 (Base)	Control input for minority-carrier injection	Receives ~0.05 A drive current to sustain 0.5 A collector current in saturation
3 (Collector)	Main current collection node	Internally bonded to metal tab; must be electrically isolated from heatsink unless circuit reference requires common-collector topology

Key Features

Feature	Design Value
Pre-selected h_FE grouping	Guarantees 100–160 h_FE at I_C = 150 mA, enabling predictable gain matching with BD140-16 in complementary pairs
Epitaxial planar structure	Ensures uniform current distribution and stable h_FE across operating temperature range (−65 to 150 °C)
Low V_CE(sat)	0.5 V at rated I_C/I_B reduces power loss and thermal stress in Class AB audio output stages
ECOPACK® compliance	Lead-free second-level interconnect meets JEDEC JESD97; supports RoHS-compliant manufacturing

Applications

Audio Power Amplifier Output Stage

Quasi-Complementary Driver

Use Scenario: Final output stage in 5–15 W stereo audio amplifiers driving 4–8 Ω speakers.

IC Role / Device Role / Timing Role: NPN power switch amplifying line-level signals into high-current speaker drive with minimal crossover distortion.

Use Value: 80 V V_CEO(sus) and 1.5 A I_C support rail voltages up to ±35 V and peak currents required for dynamic bass response.

Use Scenario: Upper-side driver in quasi-complementary output stage paired with PNP BD140-16.

IC Role / Device Role / Timing Role: NPN active element delivering positive half-cycle current while BD140-16 handles negative half-cycle.

Use Value: Matched h_FE group (100–160) ensures symmetrical gain and reduced even-order harmonic distortion.

DC Motor Speed Controller

Relay/LED Driver Interface

Use Scenario: Linear or PWM-controlled H-bridge half-bridge driver for 12 V brushed DC motors (≤10 W).

IC Role / Device Role / Timing Role: Medium-power switching transistor controlling motor current direction and magnitude.

Use Value: 12.5 W P_TOT at T_C ≤ 25 °C allows sustained operation without forced cooling in compact enclosures.

Use Scenario: Interface between microcontroller GPIO and inductive loads (e.g., 12 V relays, high-brightness LEDs).

IC Role / Device Role / Timing Role: General-purpose NPN switch translating logic-level signals into load-current paths.

Use Value: Low V_CE(sat) (0.5 V) minimizes voltage drop and heat generation during continuous conduction.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN medium-power transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BD139-10	h_FE group 63–100 (lower gain range); otherwise identical ratings and package	Suitable where lower gain suffices and tighter h_FE spread is not required	Select BD139-10 only if circuit gain margin permits lower h_FE and cost sensitivity outweighs matching needs
MJE13003	Higher V_CEO (400 V), lower I_C (1.5 A), TO-126 package, no h_FE binning	Designed for SMPS and high-voltage flyback drivers, not audio linear amplification	Not recommended for BD139-16 replacement in audio or quasi-complementary applications due to uncontrolled h_FE and different SOA

Compared with BD139-10 and MJE13003, BD139-16 provides guaranteed mid-range h_FE (100–160) essential for matched-pair audio output stages, whereas BD139-10 lacks gain consistency and MJE13003 targets high-voltage switching-not linear amplification-making BD139-16 uniquely suited for fidelity-critical analog power stages.

Availability

BD139-16 is available at Aetrix Electronics and suitable for audio amplifier output stages, quasi-complementary driver circuits, and DC motor control applications requiring stable component supply and verified h_FE grouping.

Supply support for BD139-16 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power discrete solutions.

BD139-16 belongs to ST's legacy bipolar power transistor product line, engineered specifically for cost-sensitive, medium-power linear amplification and driver applications in consumer audio and industrial controls.

FAQ

What is the difference between BD139-16 and BD139-10?

BD139-16 has a pre-selected h_FE range of 100–160 at I_C = 150 mA, while BD139-10 is binned to 63–100. All other absolute maximum ratings, package, and electrical characteristics are identical. The -16 suffix indicates tighter gain grouping for matched-pair designs.

Can BD139-16 replace BD139 in a circuit?

Yes - BD139-16 is a direct replacement for generic BD139, with the added benefit of guaranteed h_FE (100–160). No circuit modifications are needed, and performance improves in gain-sensitive applications like complementary audio outputs.

Is BD139-16 lead-free and RoHS compliant?

Yes - BD139-16 is manufactured in ST's ECOPACK® package with lead-free second-level interconnect, fully compliant with RoHS Directive 2011/65/EU and JEDEC Standard JESD97.

What is the maximum safe continuous power dissipation for BD139-16?

At case temperature ≤ 25 °C, maximum continuous power dissipation is 12.5 W. Derating is required above 25 °C at 125 mW/°C, based on R_thj-case = 10 °C/W. Ambient-limited dissipation is 1.25 W at T_amb ≤ 25 °C.

BD139-16 Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-225AA, TO-126-3

Packaging:: Tube

Product Status:: Active

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 1.5 A

Voltage - Collector Emitter Breakdown (Max):: 80 V

Vce Saturation (Max) @ Ib, Ic:: 500mV @ 50mA, 500mA

Current - Collector Cutoff (Max):: 100nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 40 @ 150mA, 2V

Power - Max:: 1.25 W

Frequency - Transition:: -

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: SOT-32-3

BD139-16 FAQ

1.How can I place an order for BD139-16 through Aetrix?

Please submit a Request for Quotation (RFQ) for BD139-16 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for BD139-16 reliable?

The price and inventory of BD139-16 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BD139-16 is usually 5 days.

3.What payment methods are accepted for BD139-16?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BD139-16 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BD139-16?

BD139-16 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BD139-16 order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for BD139-16?

For technical support, including BD139-16 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BD139-16 requirements.

6.How does Aetrix verify that BD139-16 is sourced from the original manufacturer or authorized distributors?

All BD139-16 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that BD139-16 meets industry standards.

7.What is the process for return or replacement of BD139-16?

All BD139-16 units undergo pre-shipment inspection (PSI). If there is an issue with BD139-16, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The BD139-16 part is unused and in its original packaging.

Return procedure for BD139-16:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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