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onsemi BC856ALT3
- Part No.:
- BC856ALT3
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BC856ALT3.pdf
- Description:
- TRANS PNP 65V 0.1A SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:6,889
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Product details
Overview
BC856ALT3 from onsemi is a PNP silicon general-purpose transistor in SOT-23 package, rated for −65 V VCEO, −100 mA IC continuous, and 100 MHz fT, used in low-power switching and linear amplification circuits such as level shifters, current mirrors, and discrete logic interfaces in industrial control modules.
For engineers reviewing the BC856ALT3 datasheet, pinout, applications, or equivalent options, key selection criteria include its −65 V breakdown rating, AEC-Q101 qualification for automotive-grade reliability, Pb-free RoHS-compliant packaging, and verified performance at −55 °C to +150 °C junction temperature range.
Technical Context
The BC856ALT3 belongs to the BC856A variant group within the BC856ALT1G Series, featuring hFE = 125–250 (at IC = −10 mA, VCE = −5.0 V), VCE(sat) ≤ −0.3 V (at IC = −10 mA, IB = −0.5 mA), and VBE(sat) ≤ −0.7 V under same conditions - confirming suitability for low-saturation switching.
Its thermal resistance RJA is 556 °C/W on FR-5 board and 417 °C/W on alumina substrate, with maximum power dissipation of 225 mW (derated above 25 °C), supporting stable operation in compact PCB layouts without forced cooling.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −65 V - supports high-voltage rail switching up to −65 V without breakdown in PNP common-emitter configurations. |
| IC Continuous | −100 mA - enables driving small relays, LEDs, or logic-level translation stages without external heat sinking. |
| fT | 100 MHz - sufficient for audio-frequency amplification and fast digital signal conditioning up to ~10 MHz switching. |
| hFE | 125–250 - provides predictable DC gain across production lots for bias-stable amplifier and switch designs. |
| VCE(sat) | ≤ −0.3 V @ IC/IB = 10 - ensures minimal conduction loss and efficient power delivery in saturated switching mode. |
| PD | 225 mW on FR-5 board - defines safe operating area for surface-mount placement on standard PCBs without thermal relief. |
Pinout & Package
SOT-23 (TO-236) package, 2.90 mm × 1.30 mm × 1.00 mm body size, with 1.90 mm lead pitch; thermally optimized for reflow soldering and high-density layout.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base | Control input node; requires current-limited drive (typically −0.5 mA to −5 mA) to achieve full saturation or linear operation. |
| 2 | Emiter | Common reference terminal for PNP configuration; connected to higher potential rail (e.g., −VCC or ground-referenced supply). |
| 3 | Collector | Output node; sinks current toward emitter; voltage swing limited by VCEO = −65 V and safe operating area curves. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive applications including engine control units and body electronics requiring extended temperature and lifetime reliability. |
| Pb-free, Halogen-free/BFR-free | Complies with RoHS Directive 2011/65/EU and JEDEC J-STD-609, enabling use in environmentally regulated industrial and consumer products. |
| Low VCE(sat) and tight hFE distribution | Reduces power loss and improves consistency in batch-manufactured analog circuits and discrete logic gates. |
| High fT and low Cob | Enables stable high-frequency response (up to 100 MHz) with minimal capacitive loading on driving stages. |
Applications
| Industrial Sensor Interface | Automotive Body Control Module |
|---|---|
Use Scenario: Amplifying low-level signals from NTC thermistors or Hall-effect sensors in factory automation systems. IC Role / Device Role / Timing Role: PNP small-signal amplifier configured in common-emitter topology with fixed bias network. Use Value: Delivers stable 125–250 hFE gain over −40 °C to +85 °C ambient, minimizing calibration drift in analog front-ends. |
Use Scenario: Driving LED indicators and small solenoids in door lock actuators and interior lighting controls. IC Role / Device Role / Timing Role: Low-side saturated switch controlling load current up to −100 mA from microcontroller GPIO. Use Value: Achieves ≤ −0.3 V VCE(sat) at −10 mA base drive, reducing power dissipation and thermal stress in space-constrained modules. |
| Consumer Audio Preamp Stage | Power Supply Enable Circuit |
Use Scenario: Building discrete Class-A preamplifier stages in portable headphone amplifiers and microphone boost circuits. IC Role / Device Role / Timing Role: Linear-mode PNP transistor biased for low-noise operation (NF = 10 dB @ 1 kHz). Use Value: Maintains <10 dB noise figure at IC = −0.2 mA, preserving signal integrity in battery-powered audio paths. |
Use Scenario: Enabling/disabling secondary rails in multi-output AC/DC adapters and USB-C PD power bricks. IC Role / Device Role / Timing Role: High-voltage PNP switch isolating −30 V to −65 V auxiliary supplies under MCU command. Use Value: Withstands −65 V VCEO and −80 V VCBO, ensuring robust isolation during transient overvoltage events. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP general-purpose transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC856BLT3G | hFE = 220–475 (higher gain band), same VCEO, VCE(sat), and package | Better suited for low-base-drive amplification where higher gain reduces required drive current | Select BC856BLT3G when circuit demands tighter hFE tolerance or lower base current consumption. |
| MMBT856 | Same electrical specs but non-AEC-Q101; marked "MMBT" instead of "BC"; identical SOT-23 footprint | Approved for commercial/industrial use only; not validated for automotive PPAP or temperature cycling per AEC-Q101 | Choose MMBT856 for cost-sensitive non-automotive designs where AEC-Q101 compliance is unnecessary. |
Compared with BC856BLT3G and MMBT856, the BC856ALT3 offers mid-range hFE (125–250) with guaranteed AEC-Q101 qualification - making it optimal for automotive body electronics where moderate gain stability and certified reliability are jointly required.
Availability
BC856ALT3 is available at Aetrix Electronics and suitable for industrial sensor interface, automotive body control module, and consumer audio preamp stage applications requiring stable component supply and long-term lifecycle support.
Supply support for BC856ALT3 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 is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.
The BC856ALT3 belongs to onsemi's BC856ALT1G Series of general-purpose PNP transistors, designed specifically for high-reliability discrete switching and amplification in space-constrained, thermally demanding environments.
FAQ
What is the maximum collector-emitter voltage rating for BC856ALT3?
The BC856ALT3 has a maximum collector-emitter voltage (VCEO) rating of −65 V at TA = 25 °C. This rating applies to the BC856 variant group and remains valid across the full operating temperature range of −55 °C to +150 °C, provided power dissipation limits are observed. The BC856ALT3 must not be operated beyond this voltage to prevent avalanche breakdown or permanent damage.
Is BC856ALT3 qualified for automotive applications?
Yes, the BC856ALT3 is AEC-Q101 qualified and PPAP capable, meeting the stress test requirements for automotive electronics including temperature cycling, humidity bias, and mechanical shock. It is explicitly listed in onsemi's BC856ALT1G Series documentation as compliant for use in engine control, body electronics, and infotainment subsystems.
What is the typical current gain (hFE) of BC856ALT3 at IC = −10 mA?
The BC856ALT3 exhibits hFE = 125–250 when tested at IC = −10 mA and VCE = −5.0 V, per the Electrical Characteristics table in the official onsemi datasheet. This range reflects the "A" grade binning and is guaranteed across production lots, enabling predictable bias design in amplifier and switch applications.
Does BC856ALT3 have RoHS and halogen-free compliance?
Yes, the BC856ALT3 is Pb-free, halogen-free/BFR-free, and fully RoHS compliant per Directive 2011/65/EU. The "G" suffix in the full part number BC856ALT3G confirms this compliance, and the device meets JEDEC J-STD-609 moisture sensitivity level (MSL) 1 requirements for standard reflow assembly.
What is the thermal resistance (RJA) of BC856ALT3 on a standard FR-5 PCB?
The BC856ALT3 has a thermal resistance RJA of 556 °C/W when mounted on an FR-5 board (1.0 × 0.75 × 0.062 in), with derating of 1.8 mW/°C above 25 °C ambient. This value defines the junction-to-ambient temperature rise under steady-state power dissipation and is critical for calculating safe operating limits in unventilated enclosures.
BC856ALT3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- 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):
- 15nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 125 @ 2mA, 5V
- Power - Max:
- 300 mW
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3 (TO-236)
BC856ALT3 FAQ
1.How can I place an order for BC856ALT3 through Aetrix?
Please submit a Request for Quotation (RFQ) for BC856ALT3 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 BC856ALT3 reliable?
The price and inventory of BC856ALT3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC856ALT3 is usually 5 days.
3.What payment methods are accepted for BC856ALT3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC856ALT3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC856ALT3?
BC856ALT3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC856ALT3 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 BC856ALT3?
For technical support, including BC856ALT3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC856ALT3 requirements.
6.How does Aetrix verify that BC856ALT3 is sourced from the original manufacturer or authorized distributors?
All BC856ALT3 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 BC856ALT3 meets industry standards.
7.What is the process for return or replacement of BC856ALT3?
All BC856ALT3 units undergo pre-shipment inspection (PSI). If there is an issue with BC856ALT3, 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 BC856ALT3 part is unused and in its original packaging.
Return procedure for BC856ALT3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC856ALT3 Tags
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MMBT3906LT1G
onsemi
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MMBT3904-7-F
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
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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
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MMBTA06LT1G
onsemi
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MMBT2222ALT1G
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