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onsemi BC548CTAR
- Part No.:
- BC548CTAR
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Datasheet:
-
BC548CTAR.pdf
- Description:
- TRANS NPN 30V 0.1A TO-92-3
- Quantity:
- Payment:
- Shipping:
Inventory:7,163
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Product details
Overview
BC548CTAR from ON Semiconductor is a general-purpose NPN epitaxial silicon transistor in TO-92 package, rated for 30 V VCEO, 100 mA IC, and 500 mW PC, with hFE range 420–800 (Class C), used in low-power switching and small-signal amplification circuits such as audio preamps and logic-level translators.
For engineers reviewing the BC548CTAR datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, TO-92 terminal mapping, real-world use cases, and two validated alternative transistors for design flexibility and supply continuity.
Technical Context
The BC548CTAR operates as a discrete bipolar junction transistor with fixed NPN polarity, requiring external base current control to regulate collector-emitter conduction. Its hFE classification (C-grade) ensures minimum DC current gain of 420 at IC = 2 mA and VCE = 5 V, supporting stable biasing in linear amplifier stages.
It features VCEO = 30 V and VCBO = 30 V absolute maximum ratings, enabling use in 24 V rail systems; saturation voltages are specified at 90–250 mV (IC = 10 mA, IB = 0.5 mA) and 250–600 mV (IC = 100 mA, IB = 5 mA), confirming suitability for saturated-switch applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 30 V - Maximum safe collector-emitter voltage before breakdown; defines upper limit for supply rails in switching designs. |
| hFE (min–max) | 420–800 - Guaranteed DC current gain range at IC = 2 mA, VCE = 5 V; enables predictable bias network design without gain margin overdesign. |
| IC (max) | 100 mA - Continuous collector current rating; sets hard limit for load-driving capability in relay drivers or LED switches. |
| PC | 500 mW - Total power dissipation at TA = 25°C; determines thermal derating requirements in enclosed PCB environments. |
| fT | 300 MHz - Current gain–bandwidth product at VCE = 5 V, IC = 10 mA; supports RF amplification up to ~100 MHz with usable gain. |
| VBE(sat) | 700–900 mV - Base-emitter saturation voltage across operating current range; critical for calculating base drive resistor values in switch mode. |
Pinout & Package
BC548CTAR uses the standard TO-92 3-lead plastic package with straight leads (JEDEC TO-92 compliant), featuring 1.27 mm lead pitch and through-hole mounting. Thermal resistance RθJA is 200°C/W, requiring minimal copper area for ambient-temperature operation at full power.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Collector) | Current sink node | Connected to load or higher-potential rail; carries full output current and dissipates majority of power in switching mode. |
| 2 (Base) | Control input | Receives current-limited drive signal; base resistor selection must ensure sufficient IB to saturate transistor at target IC. |
| 3 (Emitter) | Current source node | Typically tied to ground or common reference; provides return path and establishes emitter-follower or common-emitter topology. |
Key Features
| Feature | Design Value |
|---|---|
| Class C hFE grading | Guaranteed 420–800 hFE at 2 mA/5 V enables consistent gain matching across production batches in amplifier feedback networks. |
| Low VCE(sat) | 90–250 mV at 10 mA collector current minimizes conduction loss in digital logic interface and low-side switch applications. |
| 300 MHz fT | Supports high-frequency small-signal amplification up to VHF band without external neutralization or stability compensation. |
| TO-92 mechanical standardization | Enables drop-in replacement across BC546–BC550 family variants and compatibility with legacy automated insertion equipment. |
Applications
| Audio Pre-amplifier Stage | Microcontroller GPIO Level Shifter |
|---|---|
|
Use Scenario: Amplifying weak microphone signals (mV-level) to line-level (1 Vpp) before ADC sampling in portable voice recorders. IC Role / Device Role / Timing Role: Small-signal NPN amplifier in common-emitter configuration with emitter degeneration for gain stability. Use Value: 300 MHz fT and low noise figure (2–10 dB) ensure clean amplification across 20 Hz–20 kHz bandwidth without added distortion. |
Use Scenario: Translating 3.3 V logic outputs from ESP32 or STM32 to drive 5 V relays or optocouplers in industrial I/O modules. IC Role / Device Role / Timing Role: Saturated NPN switch with base resistor limiting IB to achieve forced β ≥ 10 for reliable turn-on. Use Value: VCEO = 30 V and IC = 100 mA allow direct interfacing with 24 V control systems while maintaining margin against transients. |
| LED Driver for Indicator Panels | Discrete Oscillator Core (Hartley/Colpitts) |
|
Use Scenario: Driving multi-color status LEDs (red/green/blue) on front-panel displays in test equipment with PWM dimming. IC Role / Device Role / Timing Role: Low-side constant-current switch controlled by microcontroller PWM signal. Use Value: 500 mW power rating and 100 mA IC support simultaneous drive of up to three 20 mA LEDs per channel without heatsinking. |
Use Scenario: Building tunable RF oscillator for local oscillator injection in AM/FM receiver prototypes operating at 1–30 MHz. IC Role / Device Role / Timing Role: Active device in resonant tank feedback loop providing phase-corrected gain at oscillation frequency. Use Value: 300 MHz fT and low Cob (3.5–6.0 pF) enable stable oscillation with minimal parasitic loading on LC tank components. |
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 |
|---|---|---|---|
| BC547CTA | VCEO = 45 V (vs. 30 V), same hFE Class C range, identical TO-92 package and pinout. | Higher voltage headroom supports 36 V automotive subsystems where BC548CTAR would be marginal. | Select BC547CTA when operating above 30 V or needing extra VCEO margin without changing layout or bias network. |
| 2N3904TA | Lower hFE (100–300), higher VCEO = 40 V, same TO-92 package but different pinout (E-B-C vs. C-B-E). | Requires PCB layout revision due to reversed emitter-collector terminals; not pin-compatible. | Choose 2N3904TA only if lower gain and revised layout are acceptable, e.g., in cost-sensitive consumer electronics with standardized BOMs. |
Compared with BC547CTA and 2N3904TA, BC548CTAR offers optimal balance of gain consistency (420–800), low saturation voltage, and compact 30 V rating-ideal for space-constrained 5–24 V embedded signal conditioning where gain predictability outweighs voltage overhead.
Availability
BC548CTAR is available at Aetrix Electronics and suitable for audio preamplifiers, microcontroller I/O level shifting, LED indicator drivers, and discrete RF oscillator circuits requiring stable component supply and long-term obsolescence management.
Supply support for BC548CTAR 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, with emphasis on energy efficiency and industrial reliability.
BC548CTAR belongs to the legacy BC546–BC550 NPN transistor family originally developed by Fairchild and now maintained under ON Semiconductor's discrete portfolio for general-purpose analog and switching applications.
FAQ
What is the pin configuration of BC548CTAR?
The BC548CTAR uses a standard TO-92 package with Collector–Base–Emitter pinout (flat side facing user, leads down: Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter). This matches JEDEC TO-92 mechanical specification and is consistent across all BC546–BC550 series variants. Verified via Fairchild BC546–BC550 datasheet Rev. 1.1.1, Figure 7 and 8.
What does the 'C' in BC548CTAR signify?
The 'C' in BC548CTAR denotes hFE classification: guaranteed DC current gain between 420 and 800 at IC = 2 mA and VCE = 5 V. This distinguishes it from BC548A (110–220) and BC548B (200–450), enabling precise gain selection for amplifier biasing or switching threshold control in BC548CTAR designs.
Is BC548CTAR suitable for switching 24 V loads?
Yes, BC548CTAR supports switching 24 V loads safely: its VCEO rating is 30 V and VCBO is 30 V, providing 6 V margin above 24 V nominal rails. For reliable saturation, ensure base drive delivers ≥5 mA (for 100 mA IC) and verify VCE(sat) remains ≤600 mV per datasheet conditions in BC548CTAR application.
How does BC548CTAR compare to BC547C in terms of voltage rating?
BC548CTAR has VCEO = 30 V and VCBO = 30 V, while BC547CTA specifies VCEO = 45 V and VCBO = 50 V. Both share identical hFE Class C range (420–800) and TO-92 packaging. Use BC548CTAR where 30 V margin suffices; choose BC547CTA for 36–40 V systems requiring additional headroom.
Can BC548CTAR replace BC548B in existing designs?
Yes, BC548CTAR can directly replace BC548B because both share identical package, pinout, and absolute maximum ratings; only hFE differs (BC548B: 200–450, BC548CTAR: 420–800). In amplifier circuits, higher gain may reduce required base bias resistance; in switching, no layout or drive changes are needed for BC548CTAR substitution.
BC548CTAR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Packaging:
- Tape & Box (TB)
- 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:
- 420 @ 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
BC548CTAR FAQ
1.How can I place an order for BC548CTAR through Aetrix?
Please submit a Request for Quotation (RFQ) for BC548CTAR 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 BC548CTAR reliable?
The price and inventory of BC548CTAR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC548CTAR is usually 5 days.
3.What payment methods are accepted for BC548CTAR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC548CTAR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC548CTAR?
BC548CTAR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC548CTAR 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 BC548CTAR?
For technical support, including BC548CTAR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC548CTAR requirements.
6.How does Aetrix verify that BC548CTAR is sourced from the original manufacturer or authorized distributors?
All BC548CTAR 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 BC548CTAR meets industry standards.
7.What is the process for return or replacement of BC548CTAR?
All BC548CTAR units undergo pre-shipment inspection (PSI). If there is an issue with BC548CTAR, 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 BC548CTAR part is unused and in its original packaging.
Return procedure for BC548CTAR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC548CTAR Tags
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