Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

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

onsemi BDX53BTU

Name: BDX53BTU
Brand: onsemi
SKU: BDX53BTU
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: BDX53BTU

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-220-3

Datasheet:: BDX53BTU.pdf

Description:: TRANS NPN DARL 80V 8A TO-220-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:6,138

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

BDX53BTU from ON Semiconductor (formerly Fairchild) is an NPN epitaxial silicon Darlington transistor in TO-220 package, rated for 8 A DC collector current, 80 V collector-emitter voltage, and 60 W power dissipation at TC=25°C, used in high-current linear and switching applications such as audio output stages and hammer drivers.

For engineers reviewing the BDX53BTU datasheet, pinout, applications, or equivalent options, key selection criteria include V_CEO=80 V, I_C=8 A, h_FE≥750 at I_C=3 A, V_CE(sat)=2 V, and integrated damper diode with V_F=1.8 V at 3 A - all critical for robust power switching and thermal management.

Technical Context

The BDX53BTU implements a monolithic Darlington pair structure with built-in emitter-base clamp diode and parallel damper diode, enabling high-current gain and safe inductive load switching. Its V_CEO(sus)=80 V and I_CP=12 A pulsed rating support reliable operation under transient overloads.

Thermal design is enabled by its TO-220 package with case-to-ambient thermal resistance of ~2.08°C/W (calculated from P_C=60 W and T_J(max)−T_C=125°C), and derating begins at T_C>25°C per the published power derating curve.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	80 V - Maximum continuous collector-emitter blocking voltage, defining safe operating range in switching circuits.
I_C (DC)	8 A - Continuous collector current capacity, determining maximum steady-state load drive capability.
h_FE	≥750 @ I_C=3 A - High DC current gain reduces required base drive current, easing driver stage design.
V_CE(sat)	2 V @ I_C=3 A, I_B=12 mA - Low saturation voltage minimizes conduction loss and heat generation at rated current.
P_C	60 W @ T_C=25°C - Maximum dissipated power at case temperature, requiring heatsink for sustained operation above ambient.
V_F (diode)	1.8 V @ I_F=3 A - Forward voltage of integrated damper diode, critical for flyback energy clamping in inductive loads.

Pinout & Package

BDX53BTU is housed in a standard TO-220 package with mounting tab electrically connected to collector. The device features three terminals: Base (pin 1), Collector (pin 2, tab), and Emitter (pin 3).

Pin/Terminal	Circuit Role	Design Meaning
1 (Base)	Control input	Receives low-current drive signal to enable high-current conduction between collector and emitter.
2 (Collector / Tab)	High-side power terminal	Electrically connected to metal tab; must be isolated from heatsink unless circuit ground reference permits.
3 (Emitter)	Low-side power terminal	Serves as common return path; polarity defines NPN operation and requires proper biasing relative to base.

Key Features

Feature	Design Value
Darlington configuration	Delivers h_FE ≥ 750, reducing base drive requirements by >10× versus single transistors at same current.
Integrated damper diode	Clamps inductive kickback without external components, simplifying relay or solenoid driver designs.
V_CEO(sus) = 80 V	Ensures stable blocking under surge conditions, supporting use in 48 V industrial control systems.
TO-220 mechanical standardization	Enables drop-in replacement in legacy PCB layouts and compatibility with widely available heatsinks and mounting hardware.

Applications

Audio Power Amplifiers	Relay & Solenoid Drivers
Use Scenario: Output stage in Class AB audio amplifiers delivering up to 50 W into 8 Ω loads. IC Role / Device Role / Timing Role: NPN Darlington switch providing high-current, low-distortion output drive with minimal base drive complexity. Use Value: V_CE(sat) = 2 V and h_FE ≥ 750 reduce crossover distortion and simplify driver biasing.	Use Scenario: Driving 24 V/5 A industrial relays and pneumatic solenoids with fast turn-off and back-EMF protection. IC Role / Device Role / Timing Role: High-gain switching transistor with integrated damper diode for inductive load commutation. Use Value: Built-in 1.8 V forward diode eliminates need for external flyback diode, saving board space and BOM cost.
DC Motor Controllers	Power Supply Pass Elements
Use Scenario: H-bridge low-side switches in brushed DC motor controllers for robotics and automation. IC Role / Device Role / Timing Role: NPN Darlington configured as saturated switch controlling motor current direction and magnitude. Use Value: I_C = 8 A and P_C = 60 W support continuous 24 V/3 A motor operation with appropriate heatsinking.	Use Scenario: Series pass element in linear regulated power supplies delivering up to 5 A at 12–24 V output. IC Role / Device Role / Timing Role: Voltage-controlled current source regulating output by dissipating excess input-output differential voltage. Use Value: V_CEO = 80 V and thermal derating curve allow stable operation with 40 V input headroom at 25°C case temperature.

Audio Power Amplifiers

Relay & Solenoid Drivers

Use Scenario: Output stage in Class AB audio amplifiers delivering up to 50 W into 8 Ω loads.

IC Role / Device Role / Timing Role: NPN Darlington switch providing high-current, low-distortion output drive with minimal base drive complexity.

Use Value: V_CE(sat) = 2 V and h_FE ≥ 750 reduce crossover distortion and simplify driver biasing.

Use Scenario: Driving 24 V/5 A industrial relays and pneumatic solenoids with fast turn-off and back-EMF protection.

IC Role / Device Role / Timing Role: High-gain switching transistor with integrated damper diode for inductive load commutation.

Use Value: Built-in 1.8 V forward diode eliminates need for external flyback diode, saving board space and BOM cost.

DC Motor Controllers

Power Supply Pass Elements

Use Scenario: H-bridge low-side switches in brushed DC motor controllers for robotics and automation.

IC Role / Device Role / Timing Role: NPN Darlington configured as saturated switch controlling motor current direction and magnitude.

Use Value: I_C = 8 A and P_C = 60 W support continuous 24 V/3 A motor operation with appropriate heatsinking.

Use Scenario: Series pass element in linear regulated power supplies delivering up to 5 A at 12–24 V output.

IC Role / Device Role / Timing Role: Voltage-controlled current source regulating output by dissipating excess input-output differential voltage.

Use Value: V_CEO = 80 V and thermal derating curve allow stable operation with 40 V input headroom at 25°C case temperature.

Equivalent & Alternatives

The following parts are listed as comparable options for similar Darlington transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BDX53C	V_CEO = 100 V, higher V_CEO(sus), otherwise identical pinout and gain characteristics.	Preferred in 48–72 V bus systems where higher blocking margin is required.	Select BDX53C when system max V_CE exceeds 80 V; BDX53BTU remains optimal for 24–48 V designs with tighter cost constraints.
TIP142	Same TO-220 package, but lower h_FE (1000 min vs. 750 min), higher V_CE(sat) (3 V), no integrated damper diode.	Requires external flyback diode; less suitable for compact inductive load drivers.	Choose TIP142 only if higher V_CEO (100 V) and availability outweigh need for integrated diode and lower saturation loss.

Compared with BDX53C and TIP142, the BDX53BTU offers optimal balance of 80 V blocking, integrated damper diode, and proven thermal performance in TO-220 - making it preferred for cost-sensitive 24–48 V industrial switching where reliability and layout simplicity are prioritized.

Availability

BDX53BTU is available at Aetrix Electronics and suitable for audio amplifier output stages, relay/solenoid drivers, and DC motor control applications requiring stable component supply and long-term industrial availability.

Supply support for BDX53BTU 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

ON Semiconductor (formerly Fairchild Semiconductor) is a global semiconductor supplier focused on energy-efficient electronics, with leadership in power management, analog, and discrete devices.

The BDX53BTU belongs to the BDX53 family of high-power Darlington transistors designed specifically for industrial linear and switching applications demanding high current gain, integrated protection, and rugged TO-220 packaging.

FAQ

What is the maximum continuous collector current rating for BDX53BTU?

The BDX53BTU has a maximum continuous collector current (I_C) rating of 8 A at case temperature T_C = 25°C. This rating decreases with rising case temperature per the published derating curve, reaching zero at T_C ≈ 175°C. For sustained operation, thermal design must ensure T_C remains within limits using appropriate heatsinking.

Does BDX53BTU include an integrated damper diode, and what is its forward voltage?

Yes, the BDX53BTU integrates a damper diode in parallel with the C–E junction. Its forward voltage is 1.8 V at I_F = 3 A and 2.5 V at I_F = 8 A, as specified in the datasheet. This diode enables safe commutation of inductive loads without requiring external flyback components.

What is the DC current gain (h_FE) of BDX53BTU, and under what conditions is it measured?

The BDX53BTU guarantees h_FE ≥ 750 when measured at V_CE = 3 V and I_C = 3 A. This high gain is characteristic of its Darlington configuration and significantly reduces required base drive current compared to single transistors, simplifying driver circuit design.

Is BDX53BTU pin-compatible with other members of the BDX53 family?

Yes, BDX53BTU shares identical pinout (Base–Collector–Emitter), package (TO-220), and internal architecture with BDX53, BDX53A, and BDX53C. Differences are limited to absolute maximum voltage ratings (V_CEO/V_CBO), allowing direct substitution where voltage margins permit.

What is the collector-emitter saturation voltage (V_CE(sat)) for BDX53BTU, and how does it impact power loss?

The BDX53BTU exhibits V_CE(sat) = 2 V at I_C = 3 A and I_B = 12 mA. At full 8 A DC current, conduction loss reaches up to 16 W (V_CE(sat) × I_C), necessitating adequate heatsinking. Lower V_CE(sat) than alternatives like TIP142 improves efficiency in saturated-switch applications.

BDX53BTU Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-220-3

Packaging:: Tube

Product Status:: Obsolete

Transistor Type:: NPN - Darlington

Current - Collector (Ic) (Max):: 8 A

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

Vce Saturation (Max) @ Ib, Ic:: 2V @ 12mA, 3A

Current - Collector Cutoff (Max):: 500µA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 750 @ 3A, 3V

Power - Max:: 60 W

Frequency - Transition:: -

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220-3

BDX53BTU FAQ

1.How can I place an order for BDX53BTU through Aetrix?

Please submit a Request for Quotation (RFQ) for BDX53BTU 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 BDX53BTU reliable?

The price and inventory of BDX53BTU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BDX53BTU is usually 5 days.

3.What payment methods are accepted for BDX53BTU?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BDX53BTU transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BDX53BTU?

BDX53BTU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BDX53BTU 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 BDX53BTU?

For technical support, including BDX53BTU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BDX53BTU requirements.

6.How does Aetrix verify that BDX53BTU is sourced from the original manufacturer or authorized distributors?

All BDX53BTU 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 BDX53BTU meets industry standards.

7.What is the process for return or replacement of BDX53BTU?

All BDX53BTU units undergo pre-shipment inspection (PSI). If there is an issue with BDX53BTU, 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 BDX53BTU part is unused and in its original packaging.

Return procedure for BDX53BTU:

1.Submit a request within 90 days.

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

Tech Hub

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…