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onsemi BC548BTFR
- Part No.:
- BC548BTFR
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Datasheet:
-
BC548BTFR.pdf
- Description:
- TRANS NPN 30V 0.1A TO-92-3
- Quantity:
- Payment:
- Shipping:
Inventory:9,026
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Product details
Overview
BC548BTFR from ON Semiconductor is an NPN epitaxial silicon transistor in TO-92 package, rated for VCEO = 30 V, IC = 100 mA, and PC = 500 mW, with hFE classification C (420–800) and fT = 300 MHz - used in general-purpose switching and low-noise amplification circuits in consumer electronics and industrial signal conditioning.
For engineers reviewing the BC548BTFR datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, TO-92 terminal mapping, real-world use cases, and two confirmed alternative parts with documented functional and application-level differences.
Technical Context
This device operates as a discrete bipolar junction transistor with fixed NPN polarity, optimized for linear amplification and saturated switching. Its hFE range of 420–800 at IC = 2 mA enables stable biasing in emitter-follower and common-emitter configurations, while VCE(sat) ≤ 250 mV at IC = 10 mA / IB = 0.5 mA supports low-loss switching in digital logic interfaces.
Designed for DC and low-frequency AC operation up to 300 MHz, it features Cob ≤ 6.0 pF and Cib ≈ 9 pF, making it suitable for audio preamplifiers and sensor front-ends where input/output capacitance must remain minimal. Its VEBO = 5 V and TJ = 150 °C rating support robust operation in ambient-temperature-variable environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 30 V - maximum collector-emitter voltage before breakdown; defines safe operating range in switching applications with 24 V rails. |
| IC | 100 mA - continuous DC collector current limit; sets upper bound for load-driving capability in relay drivers or LED switches. |
| hFE (Class C) | 420–800 - DC current gain at VCE = 5 V, IC = 2 mA; ensures predictable base drive requirements in amplifier bias networks. |
| fT | 300 MHz - current gain–bandwidth product; confirms usability in RF preamp stages up to ~100 MHz with adequate gain margin. |
| VCE(sat) | ≤250 mV at IC = 10 mA / IB = 0.5 mA - low saturation voltage minimizes power loss and heating in on-state switching. |
| Cob | 3.5–6.0 pF at VCB = 10 V - output capacitance limits high-frequency gain roll-off and affects stability in tuned amplifier designs. |
Pinout & Package
BC548BTFR uses the standard TO-92 3-lead plastic package with straight leads (JEDEC TO-92 compliant), designed for through-hole PCB mounting and manual prototyping. The package measures 4.6 mm × 3.3 mm × 4.0 mm (L × W × H) with 2.54 mm lead pitch.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Collector) | Main current sink node | Connected to load or supply rail in common-emitter configuration; handles full collector current path. |
| 2 (Base) | Control input terminal | Receives forward-biased current to modulate collector current; requires series resistor for stable biasing. |
| 3 (Emitter) | Current source reference node | Typically tied to ground or emitter degeneration resistor; establishes reference for VBE and hFE-dependent gain. |
Key Features
| Feature | Design Value |
|---|---|
| Switching & amplification dual use | Validated by VCE(sat) ≤ 250 mV and hFE ≥ 420 - enables single-part reuse across digital interface and analog gain stages. |
| Low noise figure (NF) | 2.0–10.0 dB at 1 kHz, RG = 2 kΩ - supports clean signal amplification in microphone preamps and sensor signal chains. |
| TO-92 tape-and-reel packaging | BC548BTFR is supplied in EIA-481-compliant tape-and-reel format - compatible with automated SMT placement equipment using through-hole adapters. |
| Complementary PNP pairing | Direct complement to BC558 - allows matched push-pull output stages and differential pair implementations without gain mismatch. |
Applications
| Audio Preamp Stage | Microcontroller GPIO Driver |
|---|---|
Use Scenario: Amplifying weak signals from electret microphones or piezoelectric sensors before ADC sampling. IC Role / Device Role / Timing Role: NPN small-signal amplifier in common-emitter configuration with emitter degeneration. Use Value: hFE = 420–800 ensures stable gain control; low NF (2.0–10.0 dB) preserves SNR in sub-10 mVpp inputs. |
Use Scenario: Driving LEDs, relays, or small solenoids from 3.3 V or 5 V microcontroller outputs. IC Role / Device Role / Timing Role: Saturated switch with base current limiting resistor. Use Value: VCE(sat) ≤ 250 mV minimizes power dissipation; IC = 100 mA supports 20 mA LED strings or 5 V/10 mA relay coils. |
| DC Power Supply Error Amplifier | Industrial Sensor Interface |
Use Scenario: Implementing error correction in linear regulator feedback loops or op-amp-based voltage references. IC Role / Device Role / Timing Role: High-gain NPN transistor in Darlington or emitter-follower topology. Use Value: hFE ≥ 420 reduces required base drive current; VCEO = 30 V accommodates 24 V system rails with margin. |
Use Scenario: Conditioning analog outputs from temperature, pressure, or proximity sensors before transmission. IC Role / Device Role / Timing Role: Low-noise buffer stage isolating sensor element from downstream circuitry. Use Value: Cob ≤ 6.0 pF prevents capacitive loading of high-impedance sensor nodes; TJ = 150 °C supports operation in enclosures up to 85 °C ambient. |
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 |
|---|---|---|---|
| BC547CTFR | VCEO = 45 V (vs. 30 V), hFE Class C same; otherwise identical TO-92 footprint and pinout. | Higher voltage headroom enables use in 36 V automotive subsystems where BC548BTFR would be marginal. | Select BC547CTFR when operating above 30 V collector supply or requiring extended VCEO margin without layout change. |
| 2N3904TFR | VCEO = 40 V, hFE = 100–300 (Class A/B), fT = 300 MHz - lower gain but tighter hFE distribution and wider VCEO. | Preferred in precision-switching applications where consistent turn-on threshold matters more than high gain. | Choose 2N3904TFR for deterministic digital switching; BC548BTFR remains optimal for analog gain-critical roles. |
Compared with BC547CTFR and 2N3904TFR, BC548BTFR offers the highest hFE among TO-92 NPN transistors in its voltage class, making it ideal for low-base-drive amplifier designs - though its 30 V VCEO requires careful rail selection versus the 40–45 V alternatives.
Availability
BC548BTFR is available at Aetrix Electronics and suitable for audio preamplification, microcontroller peripheral driving, and industrial sensor interfacing requiring stable component supply, long-term obsolescence management, and traceable sourcing.
Supply support for BC548BTFR 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 power management, analog, sensors, and discrete devices for automotive, industrial, and cloud infrastructure markets.
BC548BTFR belongs to the legacy BC5xx family originally developed by Fairchild and now maintained under ON Semiconductor's discrete transistor product line - designed for cost-sensitive, high-volume general-purpose analog and switching applications.
FAQ
What is the pin configuration of BC548BTFR?
The BC548BTFR uses the standard TO-92 pinout: Pin 1 is Collector, Pin 2 is Base, and Pin 3 is Emitter when viewing the flat side of the package with leads pointing downward. This configuration is consistent across all BC546–BC550 variants and verified in Fairchild's original datasheet Rev. 1.1.1, Figure 7 and 8.
Does BC548BTFR support low-noise audio applications?
Yes, BC548BTFR has a noise figure of 2.0–10.0 dB at 1 kHz with RG = 2 kΩ, per its official datasheet. This performance qualifies it for electret microphone preamplifiers and sensor signal conditioning where SNR preservation below 10 mVpp is critical - though BC549/BC550 offer lower NF for ultra-low-noise designs.
What is the maximum junction temperature for BC548BTFR?
The absolute maximum junction temperature (TJ) for BC548BTFR is 150 °C, as specified in the Absolute Maximum Ratings table of the BC546–BC550 datasheet. Derating is required above 25 °C ambient, with thermal resistance RθJA ≈ 200 °C/W for TO-92 in still air - meaning sustained 100 mA operation requires heatsinking or airflow above 50 °C ambient.
Is BC548BTFR RoHS compliant and lead-free?
Yes, BC548BTFR is RoHS compliant and lead-free. As part of ON Semiconductor's post-Fairchild integration, all BC5xx tape-and-reel variants including BC548BTFR meet JEDEC J-STD-609 Category 1 (lead-free) requirements and carry the "Pb-Free" marking per ON Semiconductor's compliance documentation published at www.onsemi.com.
Can BC548BTFR replace BC548BTA in a design?
Yes, BC548BTFR is functionally and electrically identical to BC548BTA - both are BC548 Class B transistors in TO-92 packages, differing only in packaging method (tape-and-reel vs. ammo). No schematic or layout changes are needed; BC548BTFR supports automated assembly, while BC548BTA suits manual or semi-automated insertion.
BC548BTFR 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):
- 30 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
BC548BTFR FAQ
1.How can I place an order for BC548BTFR through Aetrix?
Please submit a Request for Quotation (RFQ) for BC548BTFR 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 BC548BTFR reliable?
The price and inventory of BC548BTFR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC548BTFR is usually 5 days.
3.What payment methods are accepted for BC548BTFR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC548BTFR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC548BTFR?
BC548BTFR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC548BTFR 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 BC548BTFR?
For technical support, including BC548BTFR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC548BTFR requirements.
6.How does Aetrix verify that BC548BTFR is sourced from the original manufacturer or authorized distributors?
All BC548BTFR 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 BC548BTFR meets industry standards.
7.What is the process for return or replacement of BC548BTFR?
All BC548BTFR units undergo pre-shipment inspection (PSI). If there is an issue with BC548BTFR, 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 BC548BTFR part is unused and in its original packaging.
Return procedure for BC548BTFR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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