BDX54B STMicroelectronics Transistor Darlington Pair (Transistor Outline, Vertical) In Stock

BDX54B is a PNP Darlington transistor from STMicroelectronics rated at 80 V collector-emitter voltage and 8 A continuous collector current with a minimum hFE of 750, housed in a TO-220AB package. It includes an integrated freewheeling diode and base resistors for simplified inductive load switching.

OBSOLETETransistor Darlington PairVerified Jun 2026
Package / Visual Reference
BDX54BTransistor Outline, Vertical
Quick Facts
Manufacturer
STMicroelectronics
Package
Transistor Outline, Vertical
Pin Count
3
Lifecycle
OBSOLETE
Category
Transistor Darlington Pair
Price
From $0.1950(MOQ 1)
Temp Range
?°C to 150.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

Key Features

  • PNP Darlington pair delivering up to 8 A collector current with minimum DC current gain (hFE) of 750 for high-current switching from low base drive
  • Integrated built-in freewheeling diode and base-emitter resistors reduce external component count in motor and relay driver circuits
  • Rated 80 V collector-emitter voltage in a TO-220AB package, enabling efficient heat dissipation for continuous high-current operation

Applications

The BDX54B excels in PNP high-side switching applications including DC motor speed control, solenoid drivers, and power supply pass elements operating at up to 80 V and 8 A. Its integrated diode and resistors make it a drop-in solution for inductive load protection in industrial automation equipment, automotive body electronics, and linear voltage regulator designs.

Specifications

Pbfree CodeYes
YTEOL0
Collector Current-Max (IC)8A
Collector-Emitter Voltage-Max80V
ConfigurationDARLINGTON WITH BUILT-IN DIODE AND RESISTOR
DC Current Gain-Min (hFE)750
JEDEC-95 CodeTO-220AB
JESD-30 CodeR-PSFM-T3
JESD-609 Codee3
Number of Elements1
Package Body MaterialPLASTIC/EPOXY
Package ShapeRECTANGULAR
Package StyleFLANGE MOUNT
Polarity/Channel TypePNP
Power Dissipation Ambient-Max60W
Power Dissipation-Max (Abs)60W
Qualification StatusNot Qualified
Surface MountNO
Terminal FinishMATTE TIN
Terminal FormTHROUGH-HOLE
Terminal PositionSINGLE
Transistor ApplicationSWITCHING
Transistor Element MaterialSILICON
Transition Frequency-Nom (fT)20MHz
VCEsat-Max2V
PackageTransistor Outline, Vertical

Compliance & Regulatory

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

Datasheet

BDX54B Datasheet Download

Official datasheet from STMicroelectronics

Alternate & Equivalent Parts

No known alternates. Submit an RFQ and our team can suggest alternatives.

Frequently Asked Questions

What are the key electrical ratings of the BDX54B Darlington transistor?

The BDX54B is rated for a maximum collector-emitter voltage of 80 V, a continuous collector current of 8 A, and a minimum DC current gain (hFE) of 750, making it capable of switching substantial PNP high-side loads from a low-level base drive signal.

How does the BDX54B's 8 A rating compare to lower-current Darlington devices like the BD679?

The BDX54B doubles the continuous collector current of the BD679 (4 A) by providing 8 A capacity at the same 80 V collector-emitter voltage and hFE of 750, making the BDX54B the preferred choice for more demanding motor drive or power supply applications while sharing the same integrated diode and resistor configuration.

Why does the BDX54B suit inductive load applications without an external flyback diode?

The BDX54B incorporates a built-in freewheeling diode across the collector-emitter junction, clamping inductive kickback spikes when switching relays, solenoids, or DC motors at up to 8 A and 80 V, eliminating the external Schottky or fast-recovery diode typically required for protection.

What thermal management approach is recommended for the BDX54B in continuous 8 A operation?

Mounted in a TO-220AB package, the BDX54B can be bolted directly to an external heat sink using an M3 screw; at 8 A continuous and 80 V, the junction must be kept below 150 °C, so a heat sink with a thermal resistance of 5 °C/W or lower is typically required depending on ambient conditions.

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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 $0.1950
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
1+$0.4029$0.40
13+$0.3358$4.37
121+$0.3000$36.30
250+$0.2400$60.00
500+$0.2100$105.00
1000+$0.1950$195.00
pcs
Unit price: $0.4029 · Total: $0.40

In Stock · 24h Response · Worldwide Shipping

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

Response within 24 hours · Worldwide shipping

The anti-counterfeit verification gave us confidence we'd never had with other China suppliers.

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Rajesh Patel
Procurement Manager, VoltEdge Energy, India