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

onsemi BC547ARL

Name: BC547ARL
Brand: onsemi
SKU: BC547ARL
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BC547ARL

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-226-3, TO-92-3 Long Body, Formed Leads

Datasheet:: BC547ARL.pdf

Description:: TRANS NPN 45V 0.1A TO92

Quantity:: RFQ Add To RFQ list

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Inventory:8,669

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Product details

Overview

BC547ARL from onsemi is an NPN silicon general-purpose amplifier transistor in TO-92 package, rated for 45 V_CEO, 100 mA continuous collector current, and 625 mW power dissipation at 25°C ambient. It delivers DC current gain (h_FE) of 110–220 at I_C = 10 mA / V_CE = 5 V and supports small-signal amplification up to 300 MHz f_T, commonly used in low-voltage audio preamplifiers and discrete switching stages.

For engineers reviewing the BC547ARL datasheet, pinout, applications, or equivalent options, key selection criteria include its V_CEO rating, h_FE binning (A-grade), thermal resistance (R_JA = 200°C/W), and tape-and-reel packaging (2000 units) - all critical for reliability validation, PCB layout planning, and production scalability in consumer and industrial analog circuits.

Technical Context

The BC547ARL operates as a single NPN bipolar junction transistor with fixed emitter-base and collector-base junction structures optimized for linear amplification and saturated switching. Its base-emitter on voltage (V_BE(on)) is 0.55–0.77 V at I_C = 2–10 mA, and saturation voltage (V_CE(sat)) is ≤0.25 V at I_C = 10 mA / I_B = 0.5 mA, enabling efficient low-loss switching in digital logic interfaces.

Thermal design relies on its R_JA = 200°C/W and R_JC = 83.3°C/W ratings, while its f_T = 300 MHz and C_ibo = 10 pF support mid-frequency analog signal conditioning. The device is specified across −55°C to +150°C junction temperature range, with guaranteed performance at 25°C and derated operation above ambient.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	45 V - Maximum safe collector-emitter voltage before breakdown; defines rail voltage headroom in amplifier and switch designs.
I_C Continuous	100 mA - Absolute max DC collector current; sets upper limit for load-driving capability in active circuits.
h_FE (I_C = 10 mA)	110–220 - A-grade DC current gain bin; ensures predictable biasing stability in amplifier feedback networks.
f_T	300 MHz - Unity-gain bandwidth; enables use in RF preamps, oscillator buffers, and broadband signal amplification.
P_D @ T_A = 25°C	625 mW - Max ambient-rated power dissipation; determines heatsinking requirements for sustained operation.
V_CE(sat)	≤0.25 V @ I_C/I_B = 10 - Low saturation voltage minimizes conduction loss in switching applications.
R_JA	200°C/W - Junction-to-ambient thermal resistance; used to calculate temperature rise under given power load.

Pinout & Package

BC547ARL uses the TO-92 (Case 29, Style 17) through-hole plastic package with 3-pin straight-lead configuration and standardized mechanical dimensions (4.45–5.20 mm height, 4.32–5.33 mm width). Pin 1 is Collector, Pin 2 is Base, Pin 3 is Emitter - verified per onsemi mechanical outline documentation.

Pin/Terminal	Circuit Role	Design Meaning
1 - Collector	Main output current terminal	Carries amplified or switched load current; connects to supply rail or load in common-emitter configurations.
2 - Base	Control input terminal	Receives bias current to regulate collector-emitter conduction; requires current-limiting resistor in most driver circuits.
3 - Emitter	Reference/return terminal	Typically grounded or connected to emitter resistor for stabilization; establishes reference point for V_BE control.

Key Features

Feature	Design Value
NPN silicon planar structure	Enables consistent h_FE matching and low leakage (I_CES ≤ 15 nA) across production lots.
A-grade h_FE bin (110–220)	Provides tighter gain tolerance than B/C variants, reducing need for post-bias trimming in production amplifiers.
300 MHz f_T	Supports stable small-signal amplification up to VHF band without external compensation.
TO-92 tape-and-reel (2000 pcs)	Enables automated pick-and-place assembly for high-volume PCB manufacturing.
−55°C to +150°C operating range	Validates suitability for automotive under-hood and industrial control environments without derating.

Applications

Audio Preamplifier Stage	Microcontroller GPIO Driver
Use Scenario: Amplifying weak microphone or sensor signals prior to ADC sampling in portable audio devices. IC Role / Device Role / Timing Role: Discrete NPN transconductance amplifier configured in common-emitter topology with emitter degeneration. Use Value: Delivers 300 MHz f_T and low noise figure (2.0 dB) to preserve signal integrity at audio-band frequencies without op-amp complexity.	Use Scenario: Driving LEDs, relays, or MOSFET gates from 3.3 V or 5 V microcontroller outputs. IC Role / Device Role / Timing Role: Saturated switch controlled by MCU GPIO pin with base resistor limiting I_B. Use Value: V_CE(sat) ≤ 0.25 V ensures minimal voltage drop and power loss when sinking up to 100 mA loads.
Low-Voltage Power Supply Regulator	Industrial Sensor Interface
Use Scenario: Acting as pass transistor in linear voltage regulators for battery-powered instrumentation. IC Role / Device Role / Timing Role: Series-pass element controlled by error amplifier feedback loop. Use Value: 45 V V_CEO and 625 mW P_D allow regulation from 12 V input rails with adequate safety margin and thermal headroom.	Use Scenario: Converting analog sensor outputs (e.g., thermistor, photodiode) into buffered current-mode signals. IC Role / Device Role / Timing Role: Transimpedance or current-source amplifier stage with defined h_FE-based gain scaling. Use Value: Tight A-grade h_FE binning (110–220) reduces calibration drift across temperature and unit-to-unit variation.

Audio Preamplifier Stage

Microcontroller GPIO Driver

Use Scenario: Amplifying weak microphone or sensor signals prior to ADC sampling in portable audio devices.

IC Role / Device Role / Timing Role: Discrete NPN transconductance amplifier configured in common-emitter topology with emitter degeneration.

Use Value: Delivers 300 MHz f_T and low noise figure (2.0 dB) to preserve signal integrity at audio-band frequencies without op-amp complexity.

Use Scenario: Driving LEDs, relays, or MOSFET gates from 3.3 V or 5 V microcontroller outputs.

IC Role / Device Role / Timing Role: Saturated switch controlled by MCU GPIO pin with base resistor limiting I_B.

Use Value: V_CE(sat) ≤ 0.25 V ensures minimal voltage drop and power loss when sinking up to 100 mA loads.

Low-Voltage Power Supply Regulator

Industrial Sensor Interface

Use Scenario: Acting as pass transistor in linear voltage regulators for battery-powered instrumentation.

IC Role / Device Role / Timing Role: Series-pass element controlled by error amplifier feedback loop.

Use Value: 45 V V_CEO and 625 mW P_D allow regulation from 12 V input rails with adequate safety margin and thermal headroom.

Use Scenario: Converting analog sensor outputs (e.g., thermistor, photodiode) into buffered current-mode signals.

IC Role / Device Role / Timing Role: Transimpedance or current-source amplifier stage with defined h_FE-based gain scaling.

Use Value: Tight A-grade h_FE binning (110–220) reduces calibration drift across temperature and unit-to-unit variation.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN general-purpose amplifier applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC547BRL1G	B-grade h_FE bin (200–450); Pb-free TO-92 tape-and-reel	Higher gain variability; less suitable for precision biasing but better for high-current switching	Select when higher h_FE is needed and tighter gain tolerance is not required.
BC548CRL1G	Lower V_CEO (30 V); C-grade h_FE (420–800); same package	Not suitable for >30 V rails; preferred in low-voltage, high-gain digital logic interfaces	Choose only for sub-30 V systems where maximum gain outweighs voltage margin.

Compared with BC547BRL1G and BC548CRL1G, the BC547ARL offers balanced gain consistency (110–220), 45 V voltage rating, and proven thermal performance - making it optimal for general-purpose analog amplification where predictability and margin are prioritized over extreme gain or cost reduction.

Availability

BC547ARL is available at Aetrix Electronics and suitable for audio preamplifiers, microcontroller peripheral drivers, and low-voltage linear regulators requiring stable component supply, consistent h_FE binning, and TO-92 tape-and-reel compatibility.

Supply support for BC547ARL 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

onsemi (formerly ON Semiconductor) is a global semiconductor manufacturer specializing in energy-efficient power, analog, sensing, and connectivity solutions for automotive, industrial, and consumer markets.

The BC547ARL belongs to onsemi's legacy BC5xx family of general-purpose bipolar transistors, designed for cost-sensitive, high-reliability analog and switching applications where robustness, wide temperature operation, and long-term supply stability are essential.

FAQ

What is the maximum collector-emitter voltage rating for BC547ARL?

The BC547ARL has a maximum collector-emitter voltage (V_CEO) rating of 45 VDC. This value is confirmed in the Absolute Maximum Ratings table of the official onsemi datasheet (Rev. 8, August 2021) and defines the upper limit of voltage that can be safely applied between collector and emitter with the base open. Exceeding this rating risks permanent breakdown of the BC547ARL junction.

What h_FE range does BC547ARL guarantee at I_C = 10 mA?

The BC547ARL guarantees a DC current gain (h_FE) range of 110 to 220 when tested at I_C = 10 mA and V_CE = 5.0 V, per the Electrical Characteristics table in the onsemi BC546/D datasheet. This A-grade binning distinguishes BC547ARL from B- and C-variants and ensures predictable bias point stability in amplifier designs using the BC547ARL.

Is BC547ARL supplied in tape-and-reel format, and what is the reel quantity?

Yes, BC547ARL is supplied in tape-and-reel format with 2000 units per reel, as specified in the Ordering Information section of the onsemi datasheet. This packaging supports automated surface-mount assembly despite the TO-92 through-hole package - compatible with standard pick-and-place feeders equipped for radial lead components.

What is the thermal resistance from junction to ambient (R_JA) for BC547ARL?

The BC547ARL has a thermal resistance from junction to ambient (R_JA) of 200°C/W, measured under standard conditions on FR-4 PCB with no copper pour. This value is critical for calculating junction temperature rise during operation and must be used with actual power dissipation to ensure the BC547ARL remains within its −55°C to +150°C operating range.

Does BC547ARL have Pb-free construction?

Yes, the BC547ARL is manufactured with Pb-free construction, as indicated by the "G" suffix in alternate part numbers like BC547ARLG and confirmed in the onsemi Pb-Free strategy note. The device complies with RoHS Directive 2011/65/EU and is suitable for environmentally regulated electronics production requiring lead-free soldering processes.

BC547ARL Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-226-3, TO-92-3 Long Body, Formed Leads

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 100 mA

Voltage - Collector Emitter Breakdown (Max):: 45 V

Vce Saturation (Max) @ Ib, Ic:: 250mV @ 500µA, 10mA

Current - Collector Cutoff (Max):: 15nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 110 @ 2mA, 5V

Power - Max:: 625 mW

Frequency - Transition:: 300MHz

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92 (TO-226)

BC547ARL FAQ

1.How can I place an order for BC547ARL through Aetrix?

Please submit a Request for Quotation (RFQ) for BC547ARL 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 BC547ARL reliable?

The price and inventory of BC547ARL are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC547ARL is usually 5 days.

3.What payment methods are accepted for BC547ARL?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC547ARL transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC547ARL?

BC547ARL orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC547ARL 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 BC547ARL?

For technical support, including BC547ARL datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC547ARL requirements.

6.How does Aetrix verify that BC547ARL is sourced from the original manufacturer or authorized distributors?

All BC547ARL 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 BC547ARL meets industry standards.

7.What is the process for return or replacement of BC547ARL?

All BC547ARL units undergo pre-shipment inspection (PSI). If there is an issue with BC547ARL, 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 BC547ARL part is unused and in its original packaging.

Return procedure for BC547ARL:

1.Submit a request within 90 days.

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

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