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Diodes Incorporated BC857CQ-7-F
- Part No.:
- BC857CQ-7-F
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BC857CQ-7-F.pdf
- Description:
- TRANS PNP SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:3,558
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Product details
Overview
BC857CQ-7-F from Diodes Incorporated is a 45V PNP small-signal bipolar junction transistor in SOT23 package, rated for -100mA continuous collector current, -45V VCEO, and 600 typical hFE at -2mA/-5V, designed for automotive switching and audio-frequency amplification.
For engineers reviewing the BC857CQ-7-F datasheet, BC857CQ-7-F pinout, BC857CQ-7-F application, or BC857CQ-7-F equivalent, key selection criteria include AEC-Q101 qualification, SOT23 thermal resistance (357°C/W on 15mm×15mm copper), VCE(SAT) of -300mV at -10mA/-0.5mA, fT ≥100MHz, and ESD HBM rating of 4kV.
Technical Context
This PNP BJT operates with emitter-grounded configuration in linear and saturated modes, supporting DC current gain (hFE) from 420 to 800 across -2mA to -100mA, and transition frequency up to 200MHz at -10mA bias. Its breakdown ratings (VCBO = -50V, VEBO = -5V) define safe operating limits in high-side switch and amplifier topologies.
Thermal design relies on RθJA = 357°C/W (15mm×15mm PCB) and RθJL = 350°C/W, enabling stable operation from -65°C to +150°C. The device meets AEC-Q101 stress tests including HTGB, ELFR, and temperature cycling, confirming suitability for under-hood automotive modules.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | -45V - Maximum voltage sustainable between collector and emitter before avalanche conduction in common-emitter configuration. |
| IC (cont.) | -100mA - Continuous collector current limit defining maximum steady-state load drive capability in switching applications. |
| hFE | 420–800 - DC current gain range at -2mA/-5V, directly determining base drive requirements for saturation in logic-level interfaces. |
| VCE(SAT) | -300mV @ -10mA/-0.5mA - Saturation voltage defining power loss and output low-level voltage in digital switch implementations. |
| fT | 100–200MHz - Transition frequency indicating usable bandwidth for small-signal amplification up to ~100MHz at -10mA bias. |
| ESD HBM | 4,000V - Human Body Model withstand level ensuring robustness during PCB assembly and handling in automotive production lines. |
| RθJA | 357°C/W - Junction-to-ambient thermal resistance on 15mm×15mm 1oz copper, used to calculate max ambient temperature for 150°C junction limit at 310mW dissipation. |
Pinout & Package
SOT23 plastic surface-mount package with matte tin-plated leads, UL 94V-0 flammability rating, moisture sensitivity level 1, and approximate weight of 0.008g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Current sink terminal | Connected to ground or low-impedance return path; defines reference for VBE and VCE measurements. |
| 2 (Base) | Control input | Receives forward-biased current to turn on transistor; requires ~0.7V VBE(ON) at -2mA to establish conduction. |
| 3 (Collector) | Output current source | Supplies current to load when saturated; polarity inverted relative to NPN-current flows into collector in active mode. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive-grade reliability including temperature cycling, humidity testing, and mechanical shock per JESD47. |
| Green compound packaging | Halogen- and antimony-free molding compound (<900ppm Br/Cl, <1000ppm Sb), compliant with EU environmental directives. |
| Lead-free & RoHS compliance | No purposely added lead; fully compliant with Directive 2011/65/EU and J-STD-020 Level 1 moisture sensitivity. |
| Optimized for automatic insertion | SOT23 footprint and marking (K3G) support high-speed pick-and-place and optical recognition in automated SMT lines. |
Applications
| Automotive Door Module | Industrial Sensor Interface |
|---|---|
Use Scenario: Driving LED status indicators and small solenoids in door control units exposed to -40°C to +105°C ambient. IC Role / Device Role / Timing Role: PNP switch controlling 12V loads with logic-level MCU GPIO, leveraging low VCE(SAT) to minimize heat in confined enclosures. Use Value: AEC-Q101 qualification ensures field reliability; SOT23 footprint enables compact layout alongside CAN transceivers and LIN regulators. | Use Scenario: Level-shifting and buffering analog sensor outputs (e.g., thermistor networks) into 3.3V ADC inputs in factory automation PLCs. IC Role / Device Role / Timing Role: Common-emitter amplifier stage providing gain stability over industrial temperature range with predictable hFE variation. Use Value: 200MHz fT supports bandwidth beyond 10kHz sensor signals; low noise figure (2dB typ.) preserves signal integrity. |
| Consumer Audio Preamp | Power Supply Enable Circuit |
Use Scenario: Low-noise preamplifier stage in portable Bluetooth speakers handling 20Hz–20kHz audio with minimal distortion. IC Role / Device Role / Timing Role: Class-A biased PNP amplifier configured for high hFE linearity and low NF at 200µA collector current. Use Value: 2dB typical noise figure at 1kHz/2kΩ source impedance improves SNR; -650mV VBE(ON) enables precise biasing with standard resistive dividers. | Use Scenario: Enabling 5V auxiliary rails in multi-rail AC/DC adapters using microcontroller-controlled high-side switching. IC Role / Device Role / Timing Role: High-side PNP switch turning on PMOS gate drivers or LDO enable pins with fast turn-off via base discharge resistor. Use Value: -300mV VCE(SAT) limits dropout to <0.5% at 100mA; 4kV HBM ESD protects against assembly-induced damage. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP small-signal transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC857BW,115 | Same SOT323 package; identical electrical specs but different marking and reel size (10,000 pcs/reel vs. 3,000). | Preferred where board space allows larger SOT323 footprint and higher volume reels reduce cost per unit. | Select when SOT323 pad layout exists and procurement favors larger reels; no circuit redesign needed. |
| MMBT857LT1G | Higher VCEO (-50V), lower hFE min (250), same SOT23 package and AEC-Q101 qualification. | Better suited for 24V industrial systems requiring extended breakdown margin but tolerating reduced gain consistency. | Choose for 24V rail switching where -50V VCEO adds safety margin, accepting wider hFE spread. |
Compared with BC857CQ-7-F, BC857BW,115 offers identical performance in a slightly larger SOT323 package ideal for high-volume production, while MMBT857LT1G trades guaranteed high hFE for enhanced voltage ruggedness-making it preferable in 24V systems where gain tolerance is less critical than breakdown headroom.
Availability
BC857CQ-7-F is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor signal conditioning, and consumer audio preamplification requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for BC857CQ-7-F 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.
The BC857CQ belongs to Diodes' AEC-Q101-qualified small-signal transistor family, engineered specifically for automotive interior and chassis modules where reliability, thermal stability, and assembly compatibility are mandatory.
FAQ
What is the maximum allowable junction temperature for BC857CQ-7-F?
The BC857CQ-7-F has an operating junction temperature range of -65°C to +150°C. This upper limit is enforced by its thermal resistance (RθJA = 357°C/W on 15mm×15mm copper) and maximum power dissipation of 350mW. Exceeding +150°C risks permanent degradation of hFE and increased leakage currents, especially under high ambient conditions in automotive under-hood applications.
How does BC857CQ-7-F differ from the BC847CQ NPN counterpart?
The BC857CQ-7-F is the complementary PNP version of the BC847CQ NPN transistor, sharing identical SOT23 package, AEC-Q101 qualification, and absolute maximum ratings except polarity. Key differences include reversed voltage polarities (e.g., VCEO = -45V vs. +45V), opposite current flow direction, and use in high-side versus low-side switching configurations within the same automotive module.
Is BC857CQ-7-F suitable for RF amplification above 100MHz?
While BC857CQ-7-F achieves fT up to 200MHz at -10mA, its gain drops rapidly above 50MHz due to parasitic capacitance (COBO = 3pF) and package limitations. It is not recommended for RF power amplification or narrowband tuned circuits above 100MHz; instead, it serves best in broadband AF amplification and switching where phase linearity and low noise below 20kHz are prioritized.
Can BC857CQ-7-F be used in linear regulator pass elements?
No-BC857CQ-7-F is not rated for linear regulator pass applications. Its maximum power dissipation is 350mW, and VCEO = -45V is insufficient for typical 12V/24V automotive input rails with dropout margins. Additionally, lack of Safe Operating Area (SOA) curves and secondary breakdown data in the datasheet indicates it is optimized for switching and small-signal amplification, not sustained linear operation under high VCE/IC combinations.
BC857CQ-7-F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Transistor Type:
- PNP
- Current - Collector (Ic) (Max):
- -
- Voltage - Collector Emitter Breakdown (Max):
- -
- Vce Saturation (Max) @ Ib, Ic:
- 650mV @ 5mA, 100mA
- Current - Collector Cutoff (Max):
- 15nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 420 @ 2mA, 5V
- Power - Max:
- -
- Frequency - Transition:
- 200MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
BC857CQ-7-F FAQ
1.How can I place an order for BC857CQ-7-F through Aetrix?
Please submit a Request for Quotation (RFQ) for BC857CQ-7-F 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 BC857CQ-7-F reliable?
The price and inventory of BC857CQ-7-F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC857CQ-7-F is usually 5 days.
3.What payment methods are accepted for BC857CQ-7-F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC857CQ-7-F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC857CQ-7-F?
BC857CQ-7-F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC857CQ-7-F 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 BC857CQ-7-F?
For technical support, including BC857CQ-7-F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC857CQ-7-F requirements.
6.How does Aetrix verify that BC857CQ-7-F is sourced from the original manufacturer or authorized distributors?
All BC857CQ-7-F 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 BC857CQ-7-F meets industry standards.
7.What is the process for return or replacement of BC857CQ-7-F?
All BC857CQ-7-F units undergo pre-shipment inspection (PSI). If there is an issue with BC857CQ-7-F, 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 BC857CQ-7-F part is unused and in its original packaging.
Return procedure for BC857CQ-7-F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC857CQ-7-F Tags
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Diodes Incorporated
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Diodes Incorporated
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MMBT2222A-7-F
Diodes Incorporated
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Nexperia USA Inc.
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