My Inquiry
My Account
Diodes Incorporated BC857BTQ-7
- Part No.:
- BC857BTQ-7
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Bipolar Transistors
- Package:
- SOT-523
- Datasheet:
-
BC857BTQ-7.pdf
- Description:
- TRANS PNP 45V 0.1A SOT-523
- Quantity:
- Payment:
- Shipping:
Inventory:2,230
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BC857BTQ from Diodes Incorporated is a 45V PNP small-signal bipolar junction transistor in SOT523 package, rated for -100mA collector current, -45V VCEO, and qualified to AEC-Q101 for automotive use. It delivers hFE = 220–475 at -2mA/-5V, VCE(SAT) ≤ -650mV at -100mA/-5mA drive, and fT = 100MHz - deployed in automotive body control modules for load switching and signal inversion.
For engineers reviewing the BC857BTQ datasheet, BC857BTQ pinout, BC857BTQ application, or BC857BTQ equivalent, key selection criteria include its AEC-Q101 qualification, ultra-small SOT523 footprint, -45V breakdown rating, -100mA continuous current capability, and complementary pairing with BC847BTQ in bias networks and discrete amplifier stages.
Technical Context
This PNP BJT uses epitaxial planar die construction for stable gain and low leakage across -55°C to +150°C operation. Its VCEO = -45V and VEBO = -5.0V support robust reverse-bias margin in automotive 12V rail interfaces.
The device achieves fT = 100MHz at VCE = -5V and IC = -10mA, enabling use in low-power RF amplification and fast-switching logic buffers. NF = 10dB at 1kHz confirms suitability for low-noise analog front-end biasing in sensor signal conditioning.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | -45V - supports safe operation in 12V automotive systems with transient spikes up to ±45V |
| IC | -100mA - enables direct driving of small solenoids, LEDs, or logic-level inputs without external buffering |
| hFE | 220–475 @ -2mA/-5V - ensures reliable DC bias stability across production lots and temperature extremes |
| fT | 100MHz - permits use in low-frequency RF stages and high-speed digital interface circuits |
| PD | 150mW - limits thermal rise to <125°C junction temp on standard 1oz FR-4 PCB under still air |
| ESD HBM | 4000V - meets IEC 61000-4-2 Level 3 for handling robustness in automated assembly lines |
Pinout & Package
Package: SOT523 - ultra-small surface-mount plastic case (1.60 × 1.60 × 0.75 mm), UL 94V-0 rated, moisture sensitivity level 1, weight ≈ 0.002 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Current source terminal for PNP operation | Connected to higher potential rail; sets reference for base-emitter forward bias |
| 2 (Base) | Control input for minority-carrier injection | Receives negative current to turn on; requires ~-700mV VBE(SAT) at -10mA IC |
| 3 (Collector) | Current sink terminal | Drains load current to ground or lower-potential node; handles up to -100mA continuously |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive underhood applications including BCM, lighting, and HVAC control |
| Ultra-small SOT523 footprint | Reduces PCB area by >50% vs. SOT23 while maintaining thermal performance via optimized pad layout |
| Complementary NPN pairing | Direct match with BC847BTQ for push-pull output stages and differential amplifiers |
| Halogen & antimony free | Meets automotive "Green" requirements: Br+Cl <1500ppm, Sb <1000ppm |
Applications
| Automotive Body Control Module | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Switching 12V loads such as door lock actuators and interior lighting relays. IC Role / Device Role / Timing Role: PNP switch configured in common-emitter topology with base driven by MCU GPIO. Use Value: -45V VCEO withstands load-dump transients; -100mA IC drives typical solenoid coils directly. | Use Scenario: Biasing precision op-amp input stages and setting reference currents in 4–20mA transmitter circuits. IC Role / Device Role / Timing Role: Active current source/sink in discrete current mirror configurations. Use Value: hFE = 220–475 ensures stable mirror ratio across temperature; low VCE(SAT) minimizes headroom loss. |
| Low-Power RF Amplifier Stage | Logic-Level Translation Interface |
Use Scenario: Small-signal amplification in sub-100MHz ISM band receivers (e.g., TPMS, keyless entry). IC Role / Device Role / Timing Role: Common-emitter amplifier with emitter degeneration for gain stability. Use Value: fT = 100MHz enables usable gain up to 30MHz; NF = 10dB preserves SNR in weak-signal reception. | Use Scenario: Converting 3.3V logic outputs to 5V/12V-compatible levels for legacy industrial I/O modules. IC Role / Device Role / Timing Role: Inverting level shifter with pull-up resistor on collector and base driven by microcontroller. Use Value: Fast VCE(SAT) response (<100ns) supports 1MHz digital signaling; -650mV saturation ensures clean low-state definition. |
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 |
|---|---|---|---|
| BC857B,115 (Nexperia) | SOT323 package (larger than SOT523); same VCEO/IC/hFE specs; non-AEC-Q101 | Lacks automotive qualification; suitable for commercial-grade consumer electronics only | Select when AEC-Q101 is not required and board space allows larger footprint |
| MMBT5551 (ON Semiconductor) | NPN complement; VCEO = 160V, IC = -200mA; different polarity and gain profile (hFE = 80–250) | Not functionally interchangeable; used where high-voltage NPN switching is needed instead of PNP | Choose only for NPN-specific topologies requiring higher voltage margin and different gain-bandwidth trade-off |
Compared with BC857B,115, BC857BTQ offers automotive qualification and 30% smaller footprint; versus MMBT5551, it provides complementary PNP functionality with tighter hFE tolerance and lower noise - critical for precision biasing and AEC-compliant designs.
Availability
BC857BTQ is available at Aetrix Electronics and suitable for automotive body control modules, industrial sensor interfaces, low-power RF amplifiers, and logic-level translation circuits requiring stable component supply and AEC-Q101 compliance.
Supply support for BC857BTQ 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 and manufacturing operations across Asia and the Americas.
The BC857BTQ belongs to Diodes' AEC-Q101-qualified small-signal transistor product line, engineered specifically for reliability-critical automotive subsystems operating in harsh thermal and electrical environments.
FAQ
What is the maximum allowable junction temperature for BC857BTQ?
The BC857BTQ has an operating junction temperature range of -55°C to +150°C per its AEC-Q101 qualification. At ambient +85°C and 150mW dissipation, thermal resistance RθJA = 833°C/W results in ΔT ≈ 125°C - keeping TJ within spec if PCB layout follows Diodes' recommended SOT523 pad dimensions.
Is BC857BTQ pin-compatible with BC857B in SOT23?
No - BC857BTQ uses SOT523 (3-pin, 1.6×1.6mm), while BC857B uses SOT23 (3-pin, 2.9×1.3mm). Pin order (E-B-C) is identical, but mechanical fit and thermal pad layout differ significantly. Direct replacement requires PCB redesign and revalidation of thermal performance.
Does BC857BTQ support PPAP documentation for automotive programs?
Yes - BC857BTQ is PPAP-capable per Diodes Incorporated's automotive compliance framework. Full PPAP Level 3 documentation, including part submission warrant, dimensional reports, material certifications, and test data summaries, is available upon request for qualified OEM programs.
How does the noise figure of BC857BTQ impact sensor interface designs?
With NF = 10dB at IC = -0.2mA, VCE = -5V, and 1kHz bandwidth, BC857BTQ introduces minimal added noise in low-frequency sensor biasing applications. This enables accurate current-source referencing in 4–20mA loops and thermistor amplifier stages without degrading system-level SNR.
BC857BTQ-7 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- SOT-523
- 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:
- 650mV @ 5mA, 100mA
- Current - Collector Cutoff (Max):
- 15nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 220 @ 2mA, 5V
- Power - Max:
- 150 mW
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-523
BC857BTQ-7 FAQ
1.How can I place an order for BC857BTQ-7 through Aetrix?
Please submit a Request for Quotation (RFQ) for BC857BTQ-7 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 BC857BTQ-7 reliable?
The price and inventory of BC857BTQ-7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC857BTQ-7 is usually 5 days.
3.What payment methods are accepted for BC857BTQ-7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC857BTQ-7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC857BTQ-7?
BC857BTQ-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC857BTQ-7 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 BC857BTQ-7?
For technical support, including BC857BTQ-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC857BTQ-7 requirements.
6.How does Aetrix verify that BC857BTQ-7 is sourced from the original manufacturer or authorized distributors?
All BC857BTQ-7 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 BC857BTQ-7 meets industry standards.
7.What is the process for return or replacement of BC857BTQ-7?
All BC857BTQ-7 units undergo pre-shipment inspection (PSI). If there is an issue with BC857BTQ-7, 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 BC857BTQ-7 part is unused and in its original packaging.
Return procedure for BC857BTQ-7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC857BTQ-7 Tags
-
MMBT3906LT1G
onsemi
-
MMBT3904-7-F
Diodes Incorporated
-
MMBT3904LT1G
onsemi
-
MMBT3906-7-F
Diodes Incorporated
-
MMBT3904-TP
Micro Commercial Co
-
MMBT2222A-7-F
Diodes Incorporated
-
BC846BLT1G
onsemi
-
BC847B,215
Nexperia USA Inc.
-
SMMBT3904LT1G
onsemi
-
MMBT2222A-TP
Micro Commercial Co
-
MMBTA06LT1G
onsemi
-
MMBT2222ALT1G
onsemi
Tech Hub
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…
Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…
A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…
