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Nexperia USA Inc. BC857BW-QF
- Part No.:
- BC857BW-QF
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- SC-70, SOT-323
- Datasheet:
-
BC857BW-QF.pdf
- Description:
- TRANS PNP 45V 0.1A SOT-323
- Quantity:
- Payment:
- Shipping:
Inventory:2,295
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Product details
Overview
BC857BW-Q from Nexperia is a PNP general-purpose transistor in SOT323 (SC-70) package, rated for −45 V VCEO, −100 mA IC, and DC current gain (hFE) of 220–475 at VCE = −5 V and IC = −2 mA. It serves as a low-power switching or linear amplification device in automotive signal conditioning and sensor interface circuits.
For engineers reviewing the BC857BW-Q datasheet, BC857BW-Q pinout, BC857BW-Q application, or BC857BW-Q equivalent, key selection criteria include its AEC-Q101 qualification, tight hFE binning (B-grade), −45 V breakdown rating, SOT323 thermal resistance (625 K/W), and compatibility with reflow/wave soldering footprints per JEDEC SC-70 standards.
Technical Context
This device operates as a silicon PNP bipolar junction transistor with base-controlled current amplification. Its design centers on stable DC gain across temperature (−55 °C to 150 °C), low saturation voltages (VCE(sat) ≤ −250 mV at IC = −100 mA, IB = −5 mA), and robust thermal performance on FR4 PCBs.
The BC857BW-Q is optimized for discrete switching and analog amplification where precise current control and automotive-grade reliability are required. It features low leakage (ICBO ≤ −4 µA at Tj = 150 °C), 3 pF collector capacitance, and 100 MHz transition frequency (fT), enabling use in low-speed digital logic and audio-frequency signal paths.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −45 V - Maximum safe collector-emitter voltage under open-base condition; defines upper rail limit in PNP switch configurations. |
| IC | −100 mA - Continuous collector current rating; sets maximum load drive capability in active or saturated operation. |
| hFE | 220–475 - DC current gain range at VCE = −5 V, IC = −2 mA; enables predictable base drive sizing for consistent switching behavior. |
| VCE(sat) | ≤ −250 mV - Collector-emitter saturation voltage at IC = −100 mA, IB = −5 mA; determines power loss and voltage headroom in ON-state switching. |
| Rth(j-a) | 625 K/W - Junction-to-ambient thermal resistance on standard FR4 PCB; informs derating requirements for sustained 100 mA operation. |
| AEC-Q101 | Qualified - Certified for automotive applications per Stress Test Qualification for Discrete Semiconductors; supports PPAP and long-term reliability validation. |
| Cc | 3 pF - Collector capacitance at VCB = −10 V, f = 1 MHz; limits high-frequency response and affects rise/fall times in switching nodes. |
Pinout & Package
SOT323 (SC-70) plastic surface-mounted package: 1.3 mm × 1.8 mm footprint, 0.95 mm height, 3-lead configuration with gull-wing terminations. Designed for high-density PCB layouts and automated assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Current-controlled input node; requires series resistor to limit IB and ensure reliable saturation or cutoff. |
| 2 | Emitter (E) | Common terminal for PNP topology; connects to higher potential rail (e.g., VCC) in high-side switch configurations. |
| 3 | Collector (C) | Output current path; sinks load current to ground or lower-potential node when transistor is ON. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive electronics per stress test standard; eliminates need for customer-level qualification testing. |
| hFE binning (B-grade) | 220–475 gain range ensures tighter matching than standard W-grade (125–800); reduces variation in base drive requirements across production units. |
| Low VCE(sat) | ≤ −250 mV at full rated current enables <10 mW conduction loss in 100 mA loads; improves efficiency in battery-powered modules. |
| SOT323 thermal performance | 625 K/W Rth(j-a) on FR4 allows continuous 100 mA operation up to +85 °C ambient without heatsinking. |
| SC-70 footprint compatibility | Standard JEDEC SC-70 land pattern (2.65 mm × 2.35 mm) ensures drop-in placement with existing reflow profiles and stencil designs. |
Applications
| Automotive Door Module Switching | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Controlling window lift motor enable lines and mirror fold/unfold relays in door control units. IC Role / Device Role / Timing Role: PNP high-side switch driving 50–80 mA solenoid/relay coils with fast turn-off via base pull-down. Use Value: −45 V VCEO withstands load dump transients; AEC-Q101 compliance ensures 15-year field reliability in harsh cabin environments. |
Use Scenario: Amplifying low-level thermistor or RTD bridge outputs in PLC analog input modules. IC Role / Device Role / Timing Role: Linear amplifier stage providing 10–20× gain with minimal offset drift over −40 °C to +105 °C. Use Value: Stable hFE and low VBE variation (<±50 mV) maintain gain accuracy; 3 pF Cc preserves bandwidth up to 10 kHz. |
| Consumer Appliance Power Sequencing | Medical Patient Monitor LED Biasing |
Use Scenario: Enabling 3.3 V or 5 V subsystem rails in smart washing machine mainboards during boot-up sequence. IC Role / Device Role / Timing Role: Discrete PNP switch controlling PMOS gate drive or LDO enable signals with precise timing margins. Use Value: Fast saturation (ton < 50 ns typical) and low VCE(sat) minimize sequencing delay and power loss during state transitions. |
Use Scenario: Providing constant-current bias for status LEDs in portable ECG and SpO₂ devices. IC Role / Device Role / Timing Role: Current-regulated switch delivering 5–20 mA to red/green indicator LEDs with dimming control via PWM base drive. Use Value: Tight hFE binning ensures ±5% LED current consistency across batches; SOT323 size saves space on compact PCBs. |
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 |
|---|---|---|---|
| BC857BW | Non-automotive grade; lacks AEC-Q101 qualification and extended temperature screening. | Restricted to commercial/industrial use only; not suitable for automotive Tier-1 BOMs or safety-critical systems. | Select only if cost sensitivity outweighs automotive compliance requirements and lifecycle assurance. |
| MMBT3906LT1G | Higher VCEO (−40 V), wider hFE range (100–300), same SOT23 package but larger footprint (2.9 mm × 1.3 mm). | Compatible with legacy SOT23 layouts but requires PCB redesign; lower gain spread may reduce base drive margin. | Choose when migrating from SOT23-based designs and AEC-Q101 is not mandatory. |
Compared with BC857BW-Q, BC857BW offers identical electrical specs but no automotive qualification, while MMBT3906LT1G trades AEC-Q101 compliance for larger package size and looser gain control-making BC857BW-Q optimal for new automotive designs requiring validated reliability and space-constrained SOT323 integration.
Availability
BC857BW-Q is available at Aetrix Electronics and suitable for automotive body control modules, industrial sensor interfaces, and consumer appliance power sequencing requiring stable component supply and long-term manufacturing continuity.
Supply support for BC857BW-Q 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
Nexperia is a global semiconductor expert focused on essential semiconductors, delivering high-performance, reliable components for automotive, industrial, and consumer markets.
The BC857BW-Q belongs to Nexperia's AEC-Q101-qualified general-purpose transistor family, engineered specifically for robust, low-cost discrete functions in automotive electronics where reliability, thermal stability, and standardized packaging are critical.
FAQ
What is the maximum operating temperature for BC857BW-Q?
The BC857BW-Q has a maximum junction temperature (Tj) of 150 °C and an ambient operating range of −65 °C to +150 °C. Its thermal resistance (Rth(j-a)) is 625 K/W on standard FR4 PCBs, allowing continuous 100 mA operation up to +85 °C ambient without derating. Derating begins above that point per the datasheet's thermal curves.
How does BC857BW-Q differ from BC857W-Q?
BC857BW-Q is the B-gain bin variant (hFE = 220–475) of the BC857W-Q family and is AEC-Q101 qualified. BC857W-Q (standard grade) has hFE = 125–800 and no automotive qualification. Both share identical VCEO (−45 V), IC (−100 mA), package (SOT323), and pinout-only gain distribution and reliability screening differ.
Can BC857BW-Q replace BC856BW-Q in a circuit?
No-BC856BW-Q has VCEO = −65 V and VCBO = −80 V, while BC857BW-Q is rated for −45 V VCEO and −50 V VCBO. Substituting BC857BW-Q in a −65 V application risks premature breakdown. Electrical parameters like hFE and VCE(sat) are similar, but voltage ratings are not interchangeable without circuit revalidation.
What is the marking code for BC857BW-Q on the package?
The top-side marking for BC857BW-Q is "3F%", where "3F" is the type-specific identifier and "%" is a placeholder for the manufacturing site code (e.g., "3FZ" or "3FA"). This marking appears on the SOT323 package body and aligns with Nexperia's standardized SC-70 labeling scheme per Table 5 of the datasheet.
BC857BW-QF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- SC-70, SOT-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Transistor Type:
- PNP
- Current - Collector (Ic) (Max):
- 100 mA
- Voltage - Collector Emitter Breakdown (Max):
- 45 V
- Vce Saturation (Max) @ Ib, Ic:
- 400mV @ 5mA, 100mA
- Current - Collector Cutoff (Max):
- 15nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 200 @ 2mA, 5V
- Power - Max:
- 200 mW
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-323
BC857BW-QF FAQ
1.How can I place an order for BC857BW-QF through Aetrix?
Please submit a Request for Quotation (RFQ) for BC857BW-QF 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 BC857BW-QF reliable?
The price and inventory of BC857BW-QF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC857BW-QF is usually 5 days.
3.What payment methods are accepted for BC857BW-QF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC857BW-QF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC857BW-QF?
BC857BW-QF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC857BW-QF 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 BC857BW-QF?
For technical support, including BC857BW-QF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC857BW-QF requirements.
6.How does Aetrix verify that BC857BW-QF is sourced from the original manufacturer or authorized distributors?
All BC857BW-QF 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 BC857BW-QF meets industry standards.
7.What is the process for return or replacement of BC857BW-QF?
All BC857BW-QF units undergo pre-shipment inspection (PSI). If there is an issue with BC857BW-QF, 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 BC857BW-QF part is unused and in its original packaging.
Return procedure for BC857BW-QF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC857BW-QF Tags
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MMBT3906-7-F
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BC847B,215
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