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

onsemi BC546BTFR

Name: BC546BTFR
Brand: onsemi
SKU: BC546BTFR
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BC546BTFR

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-226-3, TO-92-3 (TO-226AA) Formed Leads

Datasheet:: BC546BTFR.pdf

Description:: TRANS NPN 65V 0.1A TO-92-3

Quantity:: RFQ Add To RFQ list

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Product details

Overview

BC546BTFR from ON Semiconductor is a general-purpose NPN epitaxial silicon transistor in TO-92 package, rated for 65 V V_CEO, 100 mA I_C, and 500 mW P_C, with h_FE range 200–450 (Class B), used in low-power switching and linear amplification circuits including signal conditioning stages and discrete logic interfaces.

For engineers reviewing the BC546BTFR datasheet, pinout, applications, or equivalent options, key selection considerations include its V_CEO = 65 V rating, h_FE classification (B), TO-92 mechanical compatibility, saturation voltage at 10 mA/0.5 mA drive, and noise figure suitability for audio preamp stages.

Technical Context

This device operates as a single NPN bipolar junction transistor optimized for DC-coupled amplification and on/off switching in low-voltage analog and digital subsystems. Its 150 °C maximum junction temperature and −65 to +150 °C storage range support industrial ambient operation.

It features a 300 MHz f_T at V_CE = 5 V, I_C = 10 mA, enabling use in low-frequency RF front ends and broadband audio gain blocks; Cob = 3.5–6.0 pF and Cib = 9 pF support stable biasing in high-impedance node applications.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	65 V - supports rail-to-rail switching up to ±32.5 V supply or 48 V telecom line interface without breakdown
I_C (DC)	100 mA - suitable for driving LEDs, small relays, or logic-level fanout in discrete gate implementations
h_FE Class	B (200–450) - provides predictable current gain across production lots for consistent bias point stability
V_CE(sat)	90–250 mV @ I_C = 10 mA, I_B = 0.5 mA - enables low-loss switching in battery-powered sensor nodes
f_T	300 MHz - allows use in IF amplifiers up to ~100 MHz with adequate gain margin
NF	2.0–10.0 dB @ 1 kHz - meets entry-level audio preamplifier noise requirements when biased at 200 μA

Pinout & Package

BC546BTFR uses the standard TO-92 3-lead plastic package with straight leads (JEDEC TO-92 compliant), body length 4.6 mm, lead spacing 1.27 mm, and thermal resistance R_θJA ≈ 200 °C/W.

Pin/Terminal	Circuit Role	Design Meaning
1 (Collector)	Current sink terminal	Connected to load or higher-potential rail; handles full output current and power dissipation
2 (Base)	Control input	Receives forward-biased drive current to enable conduction; requires series resistor for current limiting
3 (Emitter)	Current source terminal	Typically tied to ground or negative rail; establishes reference for V_BE bias and emitter degeneration

Key Features

Feature	Design Value
High-Voltage Capability	V_CEO = 65 V enables use in 24–48 V industrial control inputs without external clamping
Low Saturation Voltage	V_CE(sat) ≤ 250 mV at 10 mA ensures <1% voltage drop in low-side switch configurations
Controlled h_FE Spread	Class B (200–450) reduces need for individual gain trimming in production amplifier stages
Low Input Capacitance	Cib = 9 pF minimizes loading on high-impedance sensor outputs or crystal oscillator feedback paths

Applications

Audio Preamp Stage	Microcontroller GPIO Driver
Use Scenario: Amplifying weak microphone signals in portable voice recorders before ADC sampling. IC Role / Device Role / Timing Role: Discrete NPN common-emitter amplifier providing 20–40 dB voltage gain with minimal added noise. Use Value: 2.0–10.0 dB noise figure and 300 MHz f_T preserve signal fidelity up to 20 kHz while supporting compact PCB layout.	Use Scenario: Driving LED indicators or small-signal relays from 3.3 V or 5 V microcontroller I/O pins. IC Role / Device Role / Timing Role: Low-side switch translating logic-level output into controlled load current. Use Value: V_CE(sat) ≤ 250 mV at 10 mA ensures >95% efficiency in LED current path and avoids GPIO overcurrent stress.
Linear Voltage Regulator Pass Element	Discrete Logic Inverter
Use Scenario: Acting as series pass transistor in adjustable 5–12 V linear regulators for analog subsystems. IC Role / Device Role / Timing Role: Current-controlled variable resistor regulating output voltage via base bias network. Use Value: 65 V V_CEO headroom accommodates input transients up to 30 V while maintaining safe SOA operation.	Use Scenario: Implementing Schmitt-trigger or level-shifting inverters in legacy TTL/CMOS mixed-signal systems. IC Role / Device Role / Timing Role: Saturated-switch inverter with defined threshold and hysteresis via emitter feedback. Use Value: Tight h_FE spread (200–450) ensures consistent switching thresholds across production units without calibration.

Audio Preamp Stage

Microcontroller GPIO Driver

Use Scenario: Amplifying weak microphone signals in portable voice recorders before ADC sampling.

IC Role / Device Role / Timing Role: Discrete NPN common-emitter amplifier providing 20–40 dB voltage gain with minimal added noise.

Use Value: 2.0–10.0 dB noise figure and 300 MHz f_T preserve signal fidelity up to 20 kHz while supporting compact PCB layout.

Use Scenario: Driving LED indicators or small-signal relays from 3.3 V or 5 V microcontroller I/O pins.

IC Role / Device Role / Timing Role: Low-side switch translating logic-level output into controlled load current.

Use Value: V_CE(sat) ≤ 250 mV at 10 mA ensures >95% efficiency in LED current path and avoids GPIO overcurrent stress.

Linear Voltage Regulator Pass Element

Discrete Logic Inverter

Use Scenario: Acting as series pass transistor in adjustable 5–12 V linear regulators for analog subsystems.

IC Role / Device Role / Timing Role: Current-controlled variable resistor regulating output voltage via base bias network.

Use Value: 65 V V_CEO headroom accommodates input transients up to 30 V while maintaining safe SOA operation.

Use Scenario: Implementing Schmitt-trigger or level-shifting inverters in legacy TTL/CMOS mixed-signal systems.

IC Role / Device Role / Timing Role: Saturated-switch inverter with defined threshold and hysteresis via emitter feedback.

Use Value: Tight h_FE spread (200–450) ensures consistent switching thresholds across production units without calibration.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC547BTF	V_CEO = 45 V (vs. 65 V); same h_FE class, TO-92 package, tape-and-reel packaging	Not suitable for >45 V collector rail applications; otherwise functionally interchangeable in 5–24 V systems	Select BC547BTF only if system max V_CE remains below 45 V and cost optimization is prioritized
PN2222A	V_CEO = 40 V, I_C = 800 mA, h_FE = 100–300; TO-92, higher power but lower voltage rating	Better for high-current loads (e.g., solenoids), unsuitable where 65 V headroom is required	Choose PN2222A when load current exceeds 100 mA and V_CE stays under 40 V

Compared with BC547BTF and PN2222A, BC546BTFR uniquely balances 65 V breakdown voltage, 100 mA capability, and tight Class B h_FE for reliable biasing in mid-voltage analog and interface circuits where both voltage margin and gain consistency matter.

Availability

BC546BTFR is available at Aetrix Electronics and suitable for audio preamplifiers, microcontroller peripheral drivers, and linear regulator pass elements requiring stable component supply, long-term obsolescence management, and JEDEC-standard TO-92 footprint compatibility.

Supply support for BC546BTFR 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 is a global semiconductor manufacturer specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The BC546BTFR belongs to ON Semiconductor's legacy general-purpose bipolar transistor product line, designed for cost-sensitive, high-volume discrete amplification and switching applications where reliability, JEDEC compliance, and parametric consistency are essential.

FAQ

What is the maximum collector-emitter voltage rating for BC546BTFR?

The BC546BTFR has a maximum collector-emitter voltage (V_CEO) rating of 65 V. This value is specified under DC conditions at T_A = 25 °C and defines the upper limit for safe continuous operation without avalanche breakdown. Exceeding this voltage risks permanent device failure, and derating is recommended for elevated temperatures or transient conditions.

What does the 'B' in BC546BTFR indicate?

The 'B' in BC546BTFR denotes the h_FE (DC current gain) classification band, specifying a guaranteed minimum h_FE of 200 and maximum of 450 at V_CE = 5 V and I_C = 2 mA. This classification ensures predictable biasing behavior across production lots and simplifies design of stable amplifier or switch circuits without individual gain binning.

Is BC546BTFR compatible with standard TO-92 footprints?

Yes, BC546BTFR uses the JEDEC-standard TO-92 3-lead package with straight leads and 1.27 mm lead pitch, fully compatible with industry-standard TO-92 land patterns. Pin 1 is Collector, Pin 2 is Base, and Pin 3 is Emitter - matching the mechanical and electrical layout of all BC54x family variants and most generic NPN TO-92 transistors.

What is the typical noise figure of BC546BTFR and under what conditions is it measured?

The BC546BTFR exhibits a noise figure (NF) of 2.0–10.0 dB, measured at V_CE = 5 V, I_C = 200 μA, f = 1 kHz, and R_G = 2 kΩ. This range reflects unit-to-unit variation within the Class B h_FE group and makes BC546BTFR suitable for low-noise preamplifier stages in audio and sensor signal chains where sub-10 dB NF is acceptable.

Can BC546BTFR be used in switching applications, and what is its typical V_CE(sat)?

Yes, BC546BTFR is explicitly qualified for switching applications. Its typical V_CE(sat) is 90 mV at I_C = 10 mA and I_B = 0.5 mA, with a maximum of 250 mV under those conditions. This low saturation voltage minimizes power loss and heating during on-state operation, supporting efficient discrete logic-level translation and LED/relay driving.

BC546BTFR Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-226-3, TO-92-3 (TO-226AA) Formed Leads

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Transistor Type:: NPN

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

Voltage - Collector Emitter Breakdown (Max):: 65 V

Vce Saturation (Max) @ Ib, Ic:: 600mV @ 5mA, 100mA

Current - Collector Cutoff (Max):: 15nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 200 @ 2mA, 5V

Power - Max:: 500 mW

Frequency - Transition:: 300MHz

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92-3

BC546BTFR FAQ

1.How can I place an order for BC546BTFR through Aetrix?

Please submit a Request for Quotation (RFQ) for BC546BTFR 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 BC546BTFR reliable?

The price and inventory of BC546BTFR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC546BTFR is usually 5 days.

3.What payment methods are accepted for BC546BTFR?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC546BTFR transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC546BTFR?

BC546BTFR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC546BTFR 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 BC546BTFR?

For technical support, including BC546BTFR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC546BTFR requirements.

6.How does Aetrix verify that BC546BTFR is sourced from the original manufacturer or authorized distributors?

All BC546BTFR 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 BC546BTFR meets industry standards.

7.What is the process for return or replacement of BC546BTFR?

All BC546BTFR units undergo pre-shipment inspection (PSI). If there is an issue with BC546BTFR, 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 BC546BTFR part is unused and in its original packaging.

Return procedure for BC546BTFR:

1.Submit a request within 90 days.

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

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