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onsemi BC556BG
- Part No.:
- BC556BG
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-226-3, TO-92-3 Long Body
- Datasheet:
-
BC556BG.pdf
- Description:
- TRANS PNP 65V 0.1A TO92
- Quantity:
- Payment:
- Shipping:
Inventory:3,380
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Product details
Overview
BC556BG from onsemi is a PNP silicon general-purpose amplifier transistor in TO-92 package, rated for −65 V collector-emitter voltage, −100 mA continuous collector current, and 625 mW power dissipation at 25°C ambient. It delivers DC current gain (hFE) of 120–420 at −10 mA / −5 V, with fT = 280 MHz and low noise figure of 2.0 dB at 1 kHz, suitable for audio preamplifier stages and signal inversion circuits.
For engineers reviewing the BC556BG datasheet, pinout, applications, or equivalent options, key selection criteria include its −65 V VCEO, TO-92 leaded package compatibility, guaranteed hFE range across production lots, thermal resistance (RJA = 200°C/W), and Pb-free compliance per J-STD-609.
Technical Context
The BC556BG operates as a medium-power PNP bipolar junction transistor optimized for linear amplification and switching in low-to-moderate frequency analog circuits. Its design supports stable DC biasing with VBE(on) = −0.55 to −0.7 V at −2 mA and VCE(sat) ≤ −0.3 V at −10 mA/−0.5 mA drive.
Thermal performance is defined by RJC = 83.3°C/W and RJA = 200°C/W, enabling operation from −55°C to +150°C junction temperature. Small-signal parameters include Cob = 3.0–6.0 pF and fT = 280 MHz, confirming suitability for audio and sub-MHz signal conditioning.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −65 V - Maximum safe collector-emitter voltage before breakdown under open-base conditions. |
| IC (continuous) | −100 mA - Continuous collector current limit defining linear operating envelope and thermal derating baseline. |
| PD @ TA = 25°C | 625 mW - Maximum power dissipation at room ambient; requires 5.0 mW/°C derating above 25°C. |
| hFE @ −10 mA, −5 V | 120–420 - Guaranteed DC current gain range used for bias network design and gain stability margining. |
| fT | 280 MHz - Unity-gain bandwidth indicating usable small-signal amplification up to ~100 MHz with gain margin. |
| NF @ 1 kHz | 2.0 dB - Low-noise performance critical for high-fidelity preamplifier input stages. |
| Cob | 3.0–6.0 pF - Output capacitance affecting high-frequency roll-off and stability in feedback configurations. |
Pinout & Package
BC556BG uses the TO-92 (Case 29-Style 17) plastic through-hole package with bent leads, 5.20 mm maximum height, and 2.54 mm lead pitch. Pin 1 is Collector, Pin 2 is Base, Pin 3 is Emitter - confirmed per onsemi mechanical drawing and marking diagram.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Collector) | Main current sink terminal | Connected to negative supply rail in common-emitter amplifier; must withstand −65 V reverse bias. |
| 2 (Base) | Control electrode | Receives forward-biased current to modulate collector current; VBE(on) = −0.55 to −0.7 V defines bias resistor sizing. |
| 3 (Emitter) | Current source terminal | Typically tied to ground or positive rail in PNP configuration; carries full emitter current including base injection. |
Key Features
| Feature | Design Value |
|---|---|
| Pb-free TO-92 package | Complies with J-STD-609 Class 3 moisture sensitivity and RoHS Directive 2011/65/EU without lead finish. |
| Guaranteed hFE spread | 120–420 at −10 mA/−5 V ensures predictable DC bias point across production lots and temperature. |
| Low saturation voltage | VCE(sat) ≤ −0.3 V at −10 mA/−0.5 mA enables efficient switching with minimal conduction loss. |
| High VCBO | −80 V collector-base rating supports robust operation in inductive load switching and high-side driver applications. |
| Wide operating temperature | −55°C to +150°C junction range allows deployment in automotive under-hood and industrial control environments. |
Applications
| Audio Preamp Stage | Level Shifter |
|---|---|
|
Use Scenario: Amplifying weak microphone or sensor signals before ADC sampling in battery-powered instrumentation. IC Role / Device Role / Timing Role: PNP common-emitter amplifier providing inverted gain with low input-referred noise. Use Value: 2.0 dB NF and 280 MHz fT preserve signal integrity up to 20 kHz while supporting compact passive bias networks. |
Use Scenario: Converting TTL logic levels to −5 V referenced signals for legacy industrial interface modules. IC Role / Device Role / Timing Role: Active level translator using emitter-follower or common-emitter topology. Use Value: −65 V VCEO and −80 V VCBO tolerate transient overvoltage during bus contention or hot-plug events. |
| Current Mirror Reference | Discrete Logic Inverter |
|
Use Scenario: Building matched current sources in analog front-ends for sensor excitation or DAC output buffering. IC Role / Device Role / Timing Role: PNP current mirror master transistor with tightly controlled hFE and thermal tracking. Use Value: 120–420 hFE range and −55°C to +150°C operation ensure stable mirroring ratio across environmental stress. |
Use Scenario: Implementing non-inverting or inverting logic gates in repairable legacy control panels where SMT ICs are unavailable. IC Role / Device Role / Timing Role: Switching element in discrete RTL or DTL gate designs with defined propagation delay. Use Value: VCE(sat) ≤ −0.3 V and IC = −100 mA support reliable logic state transitions driving LED indicators or relay coils. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP general-purpose amplifier transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC557BG | VCEO = −45 V (vs. −65 V); hFE min = 120 at −2 mA (same test condition); fT = 320 MHz | Lower voltage rating limits use in higher-rail industrial supplies; higher fT benefits wider-bandwidth signal paths. | Select BC557BG when system rail is ≤ −45 V and small-signal bandwidth > 280 MHz is required. |
| BC558BG | VCEO = −30 V; hFE min = 120 at −2 mA; fT = 360 MHz; lower power dissipation (PD = 500 mW) | Not suitable for −65 V applications; optimized for cost-sensitive consumer audio where voltage stress is low. | Choose BC558BG only in ≤ −30 V systems prioritizing unit cost and moderate gain-bandwidth trade-offs. |
Compared with BC556BG, BC557BG offers higher fT but reduced voltage headroom, while BC558BG sacrifices both voltage rating and power capability for lower cost-making BC556BG the optimal choice for −65 V, 625 mW, and 280 MHz balanced requirements.
Availability
BC556BG is available at Aetrix Electronics and suitable for audio preamplifiers, industrial level shifters, and discrete logic inverters requiring stable component supply, long-term manufacturability, and Pb-free compliance.
Supply support for BC556BG 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 supplier specializing in energy-efficient power, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The BC556BG belongs to onsemi's legacy BC5xx PNP/NPN amplifier transistor family, designed for cost-effective, reliable discrete signal amplification and switching in through-hole-based industrial and audio equipment.
FAQ
What is the maximum collector-emitter voltage rating for BC556BG?
The BC556BG has a guaranteed VCEO rating of −65 Vdc under open-base conditions. This value is confirmed in the Absolute Maximum Ratings table of the official onsemi datasheet (BC556B/D, Rev. 3, March 2007) and defines the upper limit for safe DC biasing in common-emitter configurations. Exceeding this voltage risks avalanche breakdown and permanent device damage.
Does BC556BG have Pb-free packaging and RoHS compliance?
Yes, BC556BG is explicitly marked as a Pb-free package in the onsemi ordering information table and complies with RoHS Directive 2011/65/EU. The "G" suffix denotes green (lead-free) construction, and the device meets J-STD-609 moisture sensitivity Level 1, making it suitable for standard reflow and wave soldering processes without lead contamination concerns.
What is the DC current gain (hFE) range for BC556BG at typical operating conditions?
The BC556BG guarantees hFE between 120 and 420 when tested at −10 mA collector current and −5.0 V collector-emitter voltage (TA = 25°C). This range is specified in the Electrical Characteristics table and reflects production lot variation-designers must use the minimum (120) for worst-case bias calculations and verify stability across temperature.
Can BC556BG be used in switching applications, and what is its saturation voltage?
Yes, BC556BG is suitable for low-speed switching due to its VCE(sat) ≤ −0.3 V at −10 mA collector current and −0.5 mA base drive. This low saturation voltage minimizes conduction loss in relay drivers or LED switches. However, its fT = 280 MHz and lack of specified switching times mean it is not optimized for >100 kHz PWM applications.
What is the thermal resistance from junction to ambient (RJA) for BC556BG in TO-92 package?
The BC556BG has a maximum RJA of 200°C/W when mounted on a standard FR-4 PCB with no copper pour. This value is listed in the Thermal Characteristics section and determines how much temperature rise occurs per milliwatt of dissipated power-e.g., at 300 mW dissipation, junction temperature rises ~60°C above ambient, requiring derating above 25°C per the 5.0 mW/°C spec.
BC556BG Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-226-3, TO-92-3 Long Body
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Transistor Type:
- PNP
- Current - Collector (Ic) (Max):
- 100 mA
- Voltage - Collector Emitter Breakdown (Max):
- 65 V
- Vce Saturation (Max) @ Ib, Ic:
- 650mV @ 5mA, 100mA
- Current - Collector Cutoff (Max):
- 100nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 180 @ 2mA, 5V
- Power - Max:
- 625 mW
- Frequency - Transition:
- 280MHz
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-92 (TO-226)
BC556BG FAQ
1.How can I place an order for BC556BG through Aetrix?
Please submit a Request for Quotation (RFQ) for BC556BG 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 BC556BG reliable?
The price and inventory of BC556BG are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC556BG is usually 5 days.
3.What payment methods are accepted for BC556BG?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC556BG transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC556BG?
BC556BG orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC556BG 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 BC556BG?
For technical support, including BC556BG datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC556BG requirements.
6.How does Aetrix verify that BC556BG is sourced from the original manufacturer or authorized distributors?
All BC556BG 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 BC556BG meets industry standards.
7.What is the process for return or replacement of BC556BG?
All BC556BG units undergo pre-shipment inspection (PSI). If there is an issue with BC556BG, 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 BC556BG part is unused and in its original packaging.
Return procedure for BC556BG:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC556BG Tags
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MMBT3906LT1G
onsemi
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Diodes Incorporated
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MMBT3904LT1G
onsemi
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MMBT3906-7-F
Diodes Incorporated
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MMBT3904-TP
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
onsemi
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MMBT2222A-TP
Micro Commercial Co
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MMBTA06LT1G
onsemi
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MMBT2222ALT1G
onsemi
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