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Nexperia USA Inc. BC857BW-QX
- Part No.:
- BC857BW-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- SC-70, SOT-323
- Datasheet:
-
BC857BW-QX.pdf
- Description:
- TRANS PNP 45V 0.1A SOT-323
- Quantity:
- Payment:
- Shipping:
Inventory:3,353
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Product details
Overview
BC857BW-Q from Nexperia is a PNP general-purpose bipolar junction transistor (BJT) 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, sensor interface, and power management 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 footprint compatibility, and thermal resistance of 625 K/W on FR4 PCB.
Technical Context
This PNP BJT operates with base-emitter forward bias to control collector current flow in low-voltage, low-current analog and digital switching paths. Its design supports stable DC gain across −55 °C to +150 °C ambient, with VBE(sat) ≤ −850 mV at IC = −100 mA / IB = −5 mA and VCE(sat) ≤ −600 mV under same conditions.
The device features low leakage: ICBO ≤ −4 µA at Tj = 150 °C and IEBO ≤ −100 nA, enabling reliable operation in battery-powered and high-reliability automotive subsystems. Its 3 pF collector capacitance and 100 MHz fT support moderate-speed switching up to ~10 MHz.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −45 V - Maximum safe collector-emitter voltage before avalanche; defines usable supply rail headroom in PNP switch configurations. |
| IC | −100 mA - Continuous DC collector current limit; sets maximum load drive capability in active or saturation mode. |
| hFE | 220–475 @ VCE = −5 V, IC = −2 mA - Tighter gain bin than standard BC857W-Q (125–800); improves predictability in bias-sensitive amplifier stages. |
| VCE(sat) | ≤ −600 mV @ IC = −100 mA, IB = −5 mA - Low saturation voltage minimizes conduction loss in high-side switch applications. |
| Ptot | 200 mW @ Tamb ≤ 25 °C - Power dissipation limit on standard FR4 PCB; determines thermal derating curve for elevated ambient temperatures. |
| Rth(j-a) | 625 K/W - Junction-to-ambient thermal resistance on single-sided FR4; used to calculate max junction temperature rise under load. |
Pinout & Package
SOT323 (SC-70) plastic surface-mounted package: 1.3 mm × 1.8 mm × 0.95 mm body, 0.65 mm lead pitch, 3-terminal configuration with gull-wing leads. Optimized for reflow soldering per IPC-J-STD-020.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Control terminal; requires current-limited drive to achieve target IC; polarity must be negative relative to emitter for PNP turn-on. |
| 2 | Emitter (E) | Current source terminal; connected to higher potential (e.g., VCC) in high-side switch; provides reference for base bias network. |
| 3 | Collector (C) | Output terminal; sinks current to load/ground; reverse-biased during cutoff; voltage swing limited by VCEO rating. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Stress-tested for automotive environments including temperature cycling, HTRB, and ESD; enables use in engine control, body electronics, and ADAS modules without additional qualification. |
| B-grade hFE binning | 220–475 gain range ensures tighter matching in dual-transistor circuits and reduces need for external gain-trimming components. |
| Low VCE(sat) | ≤ −600 mV at full rated current lowers power loss and self-heating in always-on or PWM-driven loads such as LED drivers or relay coils. |
| Small SOT323 footprint | 1.3 × 1.8 mm outline saves board space in compact modules like sensor nodes and infotainment subassemblies while maintaining hand-solderability. |
Applications
| Automotive Door Module | Industrial Sensor Interface |
|---|---|
Use Scenario: Driving small solenoids and status LEDs in door lock/unlock actuation circuits. IC Role / Device Role / Timing Role: PNP high-side switch controlling 12 V loads with microcontroller GPIO-level base drive. Use Value: −45 V VCEO accommodates automotive load-dump transients; AEC-Q101 compliance ensures field reliability over 15-year vehicle lifetime. |
Use Scenario: Level-shifting and buffering analog signals from NTC thermistors or Hall-effect sensors to MCU ADC inputs. IC Role / Device Role / Timing Role: Emitter-follower amplifier providing low-output-impedance drive without inversion. Use Value: Stable hFE across −40 °C to +125 °C maintains gain accuracy; low noise figure (2–10 dB) preserves signal integrity in millivolt-range measurements. |
| Consumer Power Management | Medical Wearable Biasing |
Use Scenario: Enabling/disabling auxiliary rails (e.g., display backlight, USB port power) in portable devices. IC Role / Device Role / Timing Role: Low-leakage PNP switch isolating standby power domains with <100 nA IEBO. Use Value: −100 nA IEBO prevents unintended discharge of hold-up capacitors; 200 mW Ptot allows continuous operation at room temperature without heatsinking. |
Use Scenario: Providing precise bias current to op-amp input stages and precision reference dividers in battery-powered ECG front-ends. IC Role / Device Role / Timing Role: Current source configured with emitter resistor to set stable IC independent of VCC variation. Use Value: Tight hFE binning (220–475) reduces unit-to-unit gain drift; 150 °C max Tj supports sterilization-compatible PCB assembly processes. |
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 | Same electrical specs but not AEC-Q101 qualified; no automotive stress testing or traceability documentation. | Restricted to commercial/industrial use only; unsuitable for automotive OEM or Tier-1 designs requiring PPAP submission. | Select when cost sensitivity outweighs automotive qualification requirements and long-term supply stability is assured. |
| MMBT3906LT1G | Higher VCEO (−40 V), wider hFE range (100–300), slightly higher VCE(sat) (≤ −700 mV); SOT23 package (larger footprint). | Compatible in non-automotive switching roles but lacks AEC-Q101; larger SOT23 may conflict with layout density constraints. | Choose if existing SOT23 land pattern exists and automotive qualification is unnecessary; verify thermal performance with 350 K/W Rth(j-a). |
Compared with BC857BW-Q, BC857BW lacks automotive qualification and traceability, while MMBT3906LT1G trades AEC-Q101 compliance for lower cost and broader availability but introduces package and thermal interface differences that affect board-level reliability and layout reuse.
Availability
BC857BW-Q is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, and consumer power management requiring stable component supply, AEC-Q101 compliance, and consistent SOT323 packaging.
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 efficiency technologies, delivering high-performance, reliable discrete, logic, and MOSFET solutions for automotive, industrial, and consumer markets.
The BC857BW-Q belongs to Nexperia's AEC-Q101-qualified general-purpose transistor product line, engineered specifically for robust, space-constrained switching and amplification in harsh automotive environments.
FAQ
What is the maximum operating temperature for BC857BW-Q?
The BC857BW-Q has a maximum junction temperature (Tj) of 150 °C and a storage temperature range of −65 °C to +150 °C. Its thermal resistance is 625 K/W on standard FR4 PCB, so ambient temperature must be derated accordingly-for example, at 100 mW dissipation, Tamb must stay below +87.5 °C to keep Tj ≤ 150 °C.
Is BC857BW-Q pin-compatible with BC847BW-Q?
Yes-BC857BW-Q (PNP) and BC847BW-Q (NPN) share identical SOT323 package dimensions and pinout (1 = Base, 2 = Emitter, 3 = Collector). However, their complementary polarity means circuit topology must be inverted: BC847BW-Q sinks current from load to ground, while BC857BW-Q sources current from VCC to load.
Does BC857BW-Q support pulse operation beyond its DC ratings?
Yes-the datasheet specifies ICM = −200 mA peak collector current and IBM = −200 mA peak base current for short pulses (tp ≤ 300 µs, duty cycle ≤ 0.02). This enables brief surge handling in motor commutation or LED strobing, provided average power remains within 200 mW and thermal limits are observed.
How does the 'B' suffix in BC857BW-Q affect its gain specification?
The 'B' suffix denotes a binned hFE range of 220–475 at VCE = −5 V and IC = −2 mA-tighter than the standard 'W' grade (125–800). This binning improves consistency in bias-critical applications like current mirrors or fixed-gain amplifiers, reducing calibration effort and part-to-part variance.
BC857BW-QX 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-QX FAQ
1.How can I place an order for BC857BW-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BC857BW-QX 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-QX reliable?
The price and inventory of BC857BW-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC857BW-QX is usually 5 days.
3.What payment methods are accepted for BC857BW-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC857BW-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC857BW-QX?
BC857BW-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC857BW-QX 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-QX?
For technical support, including BC857BW-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC857BW-QX requirements.
6.How does Aetrix verify that BC857BW-QX is sourced from the original manufacturer or authorized distributors?
All BC857BW-QX 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-QX meets industry standards.
7.What is the process for return or replacement of BC857BW-QX?
All BC857BW-QX units undergo pre-shipment inspection (PSI). If there is an issue with BC857BW-QX, 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-QX part is unused and in its original packaging.
Return procedure for BC857BW-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC857BW-QX Tags
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