BD679 STMicroelectronics Transistor (Transistor Outline, Vertical) In Stock

BD679 is an NPN Darlington transistor from STMicroelectronics rated at 80 V collector-emitter voltage and 4 A collector current, featuring a built-in freewheeling diode and base resistors in a TO-126 package. Ideal for medium-power switching and motor control applications.

ACTIVETransistorVerified Jun 2026
Package / Visual Reference
BD679Transistor Outline, Vertical
Quick Facts
Manufacturer
STMicroelectronics
Package
Transistor Outline, Vertical
Pin Count
3
Lifecycle
ACTIVE
Category
Transistor
Price
From $0.1310(MOQ 10)
Temp Range
?°C to 150.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

What are the key features of BD679?

  • NPN Darlington pair with minimum DC current gain (hFE) of 750, enabling high-current switching from low-level logic signals
  • Integrated freewheeling diode and base-emitter resistors simplify circuit design and reduce external component count
  • Rated 80 V collector-emitter voltage and 4 A collector current in a compact, isolated TO-126 (SOT-32) package

What is BD679 used for?

The BD679 is well-suited for medium-power motor drive circuits, relay drivers, and solenoid control where a single transistor must handle up to 4 A from a low-current logic source. Its built-in diode provides inductive-load protection, making it a practical choice for automotive auxiliaries, industrial control panels, and power supply regulation stages operating up to 80 V.

What are the specifications of BD679?

Factory Lead Time14Weeks
YTEOL9
Case ConnectionISOLATED
Collector Current-Max (IC)4A
Collector-Emitter Voltage-Max80V
ConfigurationDARLINGTON WITH BUILT-IN DIODE AND RESISTOR
DC Current Gain-Min (hFE)750
JEDEC-95 CodeTO-126
JESD-30 CodeR-PSFM-T3
JESD-609 Codee3
Number of Elements1
Package Body MaterialPLASTIC/EPOXY
Package ShapeRECTANGULAR
Package StyleFLANGE MOUNT
Peak Reflow Temperature (Cel)NOT SPECIFIED
Polarity/Channel TypeNPN
Power Dissipation Ambient-Max40W
Power Dissipation-Max (Abs)40W
Qualification StatusNot Qualified
Surface MountNO
Terminal FinishMatte Tin (Sn)
Terminal FormTHROUGH-HOLE
Terminal PositionSINGLE
Time@Peak Reflow Temperature-Max (s)NOT SPECIFIED
Transistor ApplicationSWITCHING
Transistor Element MaterialSILICON
Transition Frequency-Nom (fT)10MHz
VCEsat-Max2.5V
## BD679 Alternates Showing resultsImage
PackageTransistor Outline, Vertical

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
ECCNEAR99
HTS Code8541.29.00.95
Country of OriginIndia

Where can I find the BD679 datasheet?

BD679 Datasheet Download

Official datasheet from STMicroelectronics

What are equivalent replacements for BD679?

Compatible alternatives and drop-in replacements for BD679:

BD679ACrimson Semiconductor Inc

Power Bipolar Transistor, 4A I(C), 80V V(BR)CEO, 1-Element, NPN, Silicon, TO-126, Plastic/Epoxy, 3 Pin

View Part →

Frequently Asked Questions

What is the maximum collector current the BD679 can handle continuously?

The BD679 is rated for a continuous collector current (IC) of 4 A, making it suitable for driving medium-power loads such as relays, solenoids, and small DC motors operating from supplies up to 80 V.

How does the BD679's minimum hFE of 750 benefit low-drive-current designs?

With a minimum DC current gain (hFE) of 750, the BD679 Darlington pair amplifies a base drive of only about 5 mA into a 4 A collector current, allowing microcontroller GPIO pins or small signal transistors to switch substantial loads without additional driver stages.

Why is the BD679 preferred over a single-stage NPN transistor for inductive load switching?

The BD679 integrates a built-in freewheeling diode and base-emitter resistors, eliminating the need for an external flyback diode when driving inductive loads like relays or motors at up to 80 V, which reduces board space and component count compared to a discrete single-stage NPN solution.

Which package does the BD679 use, and what are its key thermal mounting considerations?

The BD679 is housed in a TO-126 (SOT-32) package with an isolated case connection, allowing the heat sink to be grounded independently of the collector voltage. The package supports adequate heat dissipation for applications drawing up to 4 A at 80 V without requiring an insulating washer between the device and heat sink.

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About STMicroelectronics

STMicroelectronics is a global semiconductor leader serving customers across the spectrum of electronics applications. ST's products are found in a wide range of applications including automotive, industrial, personal electronics, and communications.

AvailabilityIn Stock
Reference Price (USD)
From $0.1310
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
10+$0.3700$3.70
100+$0.3300$33.00
500+$0.3000$150.00
1000+$0.2190$219.00
1250+$0.1320$165.00
2500+$0.1310$327.50
pcs
Unit price: $0.3700 · Total: $3.70

In Stock · 24h Response · Worldwide Shipping

Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

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Rajesh Patel
Procurement Manager, VoltEdge Energy, India