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onsemi BC547ATA
- Part No.:
- BC547ATA
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Datasheet:
-
BC547ATA.pdf
- Description:
- TRANS NPN 45V 0.1A TO-92-3
- Quantity:
- Payment:
- Shipping:
Inventory:548
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Product details
Overview
BC547ATA from ON Semiconductor is an NPN epitaxial silicon transistor designed for general-purpose switching and low-noise amplification in discrete analog circuits, with VCEO = 45 V, IC = 100 mA, PC = 500 mW, and hFE range of 110–220 (Class A), commonly used in audio preamplifiers, sensor interface stages, and digital logic level translation.
For engineers reviewing the BC547ATA datasheet, pinout, applications, or equivalent options, this page delivers verified package mapping (TO-92), terminal assignment (C-B-E), hFE classification, saturation voltage behavior, and validated alternatives for legacy design continuity and BOM rationalization.
Technical Context
The BC547ATA belongs to the BC546–BC550 family of through-hole NPN transistors fabricated using epitaxial planar process technology. It operates as a current-controlled switch or linear amplifier with fixed junction temperature limit of 150°C and storage range from −65°C to +150°C.
Its DC current gain (hFE) is specified at VCE = 5 V and IC = 2 mA, with Class A variant exhibiting 110–220 gain; saturation voltages are characterized at two bias points (IC = 10 mA/IB = 0.5 mA and IC = 100 mA/IB = 5 mA), supporting both small-signal and medium-current switching use cases.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum collector-emitter voltage before breakdown; defines safe operating voltage headroom in low-voltage power supply rails and signal coupling applications. |
| IC (DC) | 100 mA - Continuous collector current rating; sets upper limit for load-driving capability in relay drivers and LED switches. |
| PC | 500 mW - Total power dissipation at TA = 25°C; determines thermal derating requirements on PCBs without heatsinking. |
| hFE (Class A) | 110–220 - DC current gain range at VCE = 5 V, IC = 2 mA; enables predictable base drive calculation for stable biasing in amplifier stages. |
| VCE(sat) | 90–250 mV @ IC = 10 mA / IB = 0.5 mA - Low saturation voltage ensures minimal voltage drop and power loss when used as a saturated switch. |
| fT | 300 MHz - Current gain–bandwidth product at VCE = 5 V, IC = 10 mA; supports RF front-end and wideband amplifier designs up to ~100 MHz. |
| NF | 2.0–10.0 dB @ VCE = 5 V, IC = 200 μA, f = 1 kHz - Noise figure suitable for low-level signal amplification in microphone preamps and sensor conditioning circuits. |
Pinout & Package
BC547ATA is housed in a TO-92 3-lead plastic package with straight leads (JEDEC TO-92 compliant), optimized for through-hole mounting and manual prototyping. The case outline matches Fairchild/ON Semiconductor standard dimensions (Figure 7 & 8), with lead spacing of 0.2 inch (5.08 mm).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Top View, Flat Side Facing Up) | Collector | Main current output terminal; connects to load or supply rail in common-emitter configurations. |
| 2 | Base | Control input; requires current-limited drive (typically via resistor) to bias transistor into active or saturation region. |
| 3 | Emitter | Current return path; often tied to ground or negative rail; provides reference for VBE and hFE-based calculations. |
Key Features
| Feature | Design Value |
|---|---|
| Switching & amplification dual role | Validated across VCE = 5 V to 45 V and IC = 0.2 mA to 100 mA, enabling reuse in both digital control and analog signal paths. |
| Low VCE(sat) at moderate currents | ≤250 mV at IC = 10 mA / IB = 0.5 mA reduces conduction loss and self-heating in battery-powered switching nodes. |
| Class A hFE binning | 110–220 gain range ensures consistent DC bias stability in production-grade amplifier circuits without individual trimming. |
| TO-92 mechanical compatibility | Standardized footprint allows direct substitution with BC546/BC548/BC549 variants and legacy designs using JEDEC-compliant sockets or hand-soldered layouts. |
| Low-noise operation | 2.0–10.0 dB noise figure at 1 kHz supports high-fidelity audio preamplifier stages where SNR preservation is critical. |
Applications
| Audio Preamp Stage | Sensor Signal Conditioning |
|---|---|
|
Use Scenario: Amplifying weak signals from electret microphones or piezoelectric sensors in portable voice recorders. IC Role / Device Role / Timing Role: Discrete NPN transistor configured in common-emitter topology to provide 20–40 dB voltage gain with minimal added noise. Use Value: BC547ATA's 2.0–10.0 dB noise figure and 110–220 hFE enable clean amplification of sub-millivolt inputs without requiring op-amp ICs. |
Use Scenario: Converting low-level resistance or current changes from thermistors, phototransistors, or strain gauges into measurable voltage swings. IC Role / Device Role / Timing Role: Transconductance amplifier stage converting sensor current to voltage while providing isolation and gain. Use Value: With VBE(on) = 580–700 mV and predictable hFE, BC547ATA delivers repeatable transfer characteristics across temperature for analog front-end linearity. |
| Digital Logic Level Translation | Relay / LED Driver Switch |
|
Use Scenario: Interfacing 3.3 V microcontroller GPIOs to 5 V or 12 V logic families or peripheral inputs. IC Role / Device Role / Timing Role: Saturated NPN switch translating logic-high states by pulling down target input lines or enabling pull-up networks. Use Value: VCE(sat) ≤250 mV at IC = 10 mA ensures reliable low-state voltage (<0.3 V) compatible with TTL and CMOS thresholds. |
Use Scenario: Driving 5–12 V relays or high-brightness LEDs from MCU outputs in industrial control panels and lighting modules. IC Role / Device Role / Timing Role: Medium-current switch handling up to 100 mA load current with controlled turn-on/turn-off via base resistor. Use Value: 500 mW power rating and 45 V VCEO allow safe operation with inductive kickback suppression and margin over typical 12 V supply rails. |
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 |
|---|---|---|---|
| BC547BTA | Higher hFE range (200–450); otherwise identical VCEO, IC, PC, and TO-92 package. | Better suited for low-base-drive applications (e.g., high-impedance sensor buffers) where higher gain reduces required base current. | Select BC547BTA when circuit bias stability demands tighter hFE tolerance or lower input loading; BC547ATA remains optimal for predictable mid-gain designs. |
| PN2222A | VCEO = 40 V (vs. 45 V), hFE = 100–300 (Class A/B), same TO-92 package and pinout (C-B-E). | Widely available but slightly lower voltage rating; may require layout review if operating near 45 V rails. | Use PN2222A only after verifying VCEO margin in target application; BC547ATA offers superior voltage headroom and documented noise performance. |
Compared with BC547BTA and PN2222A, BC547ATA provides the most balanced combination of voltage rating, gain predictability, and low-noise suitability for cost-sensitive analog and mixed-signal designs requiring long-term component availability and legacy compatibility.
Availability
BC547ATA is available at Aetrix Electronics and suitable for audio preamplifiers, sensor interface circuits, and digital logic level translation requiring stable component supply, long-life obsolescence management, and through-hole manufacturing compatibility.
Supply support for BC547ATA 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, and discrete components for automotive, industrial, and consumer applications.
BC547ATA belongs to the legacy BC5xx family originally developed by Fairchild Semiconductor and now maintained under ON Semiconductor's discrete transistor portfolio, targeting cost-effective, robust, and widely supported general-purpose bipolar junction transistor solutions.
FAQ
What is the pin configuration of BC547ATA?
The BC547ATA uses a standard TO-92 package with pin 1 as Collector, pin 2 as Base, and pin 3 as Emitter when viewed with the flat side facing up and leads pointing downward. This C-B-E arrangement is consistent across all BC546–BC550 variants and confirmed in the official ON Semiconductor datasheet Rev. 1.1.1.
What does the 'A' suffix in BC547ATA indicate?
The 'A' in BC547ATA denotes the hFE gain classification-specifically, a DC current gain range of 110–220 at VCE = 5 V and IC = 2 mA. The 'TA' suffix indicates TO-92 packaging in ammo pack format, distinguishing it from bulk (BU) or tape-and-reel (TFR) variants.
Can BC547ATA replace BC547B or BC547C in existing designs?
BC547ATA can replace BC547B or BC547C only if the circuit tolerates lower hFE (110–220 vs. 200–450 or 420–800). Gain-dependent bias points or feedback loops may require recalculating base resistors; verify VCE(sat) and fT remain sufficient for the intended switching or amplification frequency.
Is BC547ATA suitable for RF applications?
Yes-BC547ATA has a current gain–bandwidth product (fT) of 300 MHz, making it usable in VHF and low-UHF amplifier stages (e.g., 30–100 MHz receivers). However, its Cob = 3.5–6.0 pF and noise figure increase above 1 MHz, so it is best applied in narrowband or low-gain RF front ends rather than wideband or high-frequency oscillators.
Does BC547ATA have built-in ESD protection?
No-BC547ATA is a bare-die bipolar junction transistor without integrated ESD protection diodes. External protection (e.g., series base resistor + clamping diode) is recommended in handling and PCB layout, especially in environments with >2 kV HBM exposure risk, per ON Semiconductor's reliability guidelines for discrete transistors.
BC547ATA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Packaging:
- Cut Tape (CT)
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 100 mA
- Voltage - Collector Emitter Breakdown (Max):
- 45 V
- Vce Saturation (Max) @ Ib, Ic:
- 600mV @ 5mA, 100mA
- Current - Collector Cutoff (Max):
- 15nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 110 @ 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
BC547ATA FAQ
1.How can I place an order for BC547ATA through Aetrix?
Please submit a Request for Quotation (RFQ) for BC547ATA 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 BC547ATA reliable?
The price and inventory of BC547ATA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC547ATA is usually 5 days.
3.What payment methods are accepted for BC547ATA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC547ATA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC547ATA?
BC547ATA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC547ATA 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 BC547ATA?
For technical support, including BC547ATA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC547ATA requirements.
6.How does Aetrix verify that BC547ATA is sourced from the original manufacturer or authorized distributors?
All BC547ATA 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 BC547ATA meets industry standards.
7.What is the process for return or replacement of BC547ATA?
All BC547ATA units undergo pre-shipment inspection (PSI). If there is an issue with BC547ATA, 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 BC547ATA part is unused and in its original packaging.
Return procedure for BC547ATA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC547ATA Tags
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MMBT3906LT1G
onsemi
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MMBT3904-7-F
Diodes Incorporated
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onsemi
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MMBT3906-7-F
Diodes Incorporated
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Micro Commercial Co
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MMBT2222A-7-F
Diodes Incorporated
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BC846BLT1G
onsemi
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BC847B,215
Nexperia USA Inc.
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SMMBT3904LT1G
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MMBT2222A-TP
Micro Commercial Co
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MMBTA06LT1G
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