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Nexperia USA Inc. BC817W-QX
- Part No.:
- BC817W-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- SC-70, SOT-323
- Datasheet:
-
BC817W-QX.pdf
- Description:
- TRANS NPN 45V 0.5A SOT-323
- Quantity:
- Payment:
- Shipping:
Inventory:2,471
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Product details
Overview
BC817W-Q from Nexperia is an AEC-Q101-qualified NPN general-purpose transistor in SOT323 (SC-70) package, rated for 45 V VCEO, 500 mA continuous collector current, and DC current gain (hFE) of 100–600 at IC = 100 mA, VCE = 1 V. It serves as a compact, automotive-grade switching and amplification device in space-constrained PCBs for engine control modules and body electronics.
For engineers reviewing the BC817W-Q datasheet, BC817W-Q pinout, BC817W-Q application, or BC817W-Q equivalent, this page delivers verified electrical parameters, thermal derating behavior, base-emitter saturation voltage under load, and validated automotive qualification status - all critical for reliability-critical discrete selection.
Technical Context
This NPN bipolar junction transistor operates in linear or saturated switching mode with VCEO = 45 V and VCBO = 50 V, enabling use in 12 V/24 V automotive supply rails with margin. Its pulsed IC rating reaches 1 A (tp ≤ 1 ms), supporting short-duration surge handling in relay drivers and LED flash circuits.
Thermal performance is defined by Rth(j-a) = 625 K/W on standard FR4 (single-sided copper), dropping to 431 K/W with 1 cm² collector pad - a key design constraint for sustained 500 mA operation. The device exhibits fT = 100 MHz at VCE = 5 V, IC = 10 mA, confirming suitability for low-frequency signal amplification up to ~10 MHz.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage with base open; sets upper rail limit for 24 V automotive systems. |
| IC (continuous) | 500 mA - Continuous DC collector current at Tamb = 25 °C; defines steady-state load drive capability. |
| hFE | 100–600 - DC current gain range at VCE = 1 V, IC = 100 mA; determines required base drive for saturation. |
| VCE(sat) | ≤ 700 mV at IC = 500 mA, IB = 50 mA - Low saturation voltage minimizes power loss in switching applications. |
| Ptot | 200 mW (standard footprint) - Total power dissipation limit at Tamb ≤ 25 °C; governs thermal layout requirements. |
| fT | 100 MHz - Transition frequency at VCE = 5 V, IC = 10 mA; confirms usable bandwidth for audio and low-speed digital buffering. |
| Cc | 3 pF - Collector capacitance at VCB = 10 V; impacts high-frequency response and switching speed in RF-adjacent circuits. |
Pinout & Package
SOT323 (SC-70) plastic surface-mounted package: ultra-compact 3-pin outline measuring 2.2 mm × 1.35 mm × 0.95 mm (L × W × H), optimized for high-density automotive PCBs with reflow-compatible solder pads.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Current-controlled input node; requires ≥50 mA base drive for full 500 mA collector saturation. |
| 2 | Emitter (E) | Common reference terminal; internally connected to PCB ground plane in most switching configurations. |
| 3 | Collector (C) | High-side load connection point; thermally coupled to PCB copper for heat dissipation in SOT323 footprint. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive underhood environments per stress test standard - enables use without additional qualification effort. |
| Three hFE variants | BC817-16W-Q (100–250), BC817-25W-Q (160–400), BC817-40W-Q (250–600) - allows precise gain matching to circuit stability and drive strength needs. |
| Low VCE(sat) | ≤700 mV at IC/IB = 10 - reduces conduction loss by >30% vs. legacy general-purpose transistors at 500 mA. |
| Thermal robustness | Tj(max) = 150 °C and Tstg = −65 to +150 °C - supports operation across extended automotive temperature ranges. |
| SC-70 footprint compatibility | Standardized JEDEC SC-70 / SOT323 land pattern - ensures drop-in replacement and automated assembly compatibility. |
Applications
| Engine Control Unit (ECU) Signal Conditioning | Automotive Body Control Module (BCM) Switching |
|---|---|
|
Use Scenario: Amplifying low-level sensor signals (e.g., crankshaft position Hall effect output) before ADC sampling in ECU mainboard. IC Role / Device Role / Timing Role: Linear-mode NPN amplifier with fixed bias network; provides 20–30 dB voltage gain at <100 kHz. Use Value: Maintains signal integrity with hFE stability across −40 to +125 °C ambient, avoiding gain drift-induced timing errors. |
Use Scenario: Driving 12 V solenoid valves and incandescent lamps in door lock, window lift, and mirror control circuits. IC Role / Device Role / Timing Role: Saturated-switching transistor with forced β = 10; toggles loads in <10 µs with minimal shoot-through risk. Use Value: Delivers reliable 500 mA load current at VCE(sat) ≤ 700 mV, reducing thermal stress versus higher-VCE(sat) alternatives. |
| LED Brake Light Driver | Infotainment System Audio Preamp Stage |
|
Use Scenario: Constant-current switching for high-brightness red LEDs in rear lighting clusters with PWM dimming. IC Role / Device Role / Timing Role: Fast-switching NPN switch operating at 1–2 kHz PWM; handles peak IC = 1 A pulses. Use Value: Withstands repetitive 1 A pulses (tp ≤ 1 ms) and maintains <1 µs turn-off delay, ensuring clean PWM edge fidelity. |
Use Scenario: Low-noise preamplifier stage for analog audio inputs (e.g., microphone or line-in) in head unit front-end. IC Role / Device Role / Timing Role: Common-emitter small-signal amplifier biased at IC = 1–5 mA; operates below fT/10 for stable gain. Use Value: Achieves <0.5% THD at 1 kHz due to low Cc (3 pF) and predictable hFE variation, preserving audio fidelity. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN general-purpose transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC847BW-Q | Lower VCEO (45 V same), lower IC (100 mA), higher hFE (110–800), same SOT323 package | Not suitable for 500 mA loads; better for low-power signal amplification only | Select when gain precision > current drive; avoid for switching >200 mA |
| MMBT3904-7-F | Same VCEO (40 V), same IC (200 mA), hFE 100–300, SOT23 package (larger footprint) | Requires PCB redesign due to SOT23 vs. SOT323; insufficient for 500 mA continuous loads | Use only if SOT23 is already standardized; not a functional substitute for BC817W-Q's current rating |
Compared with BC847BW-Q and MMBT3904-7-F, BC817W-Q uniquely combines 500 mA continuous current, AEC-Q101 qualification, and SOT323 size - making it the sole option among these three for space-constrained automotive switching above 300 mA.
Availability
BC817W-Q is available at Aetrix Electronics and suitable for automotive engine control units, body control modules, and LED lighting systems requiring stable component supply with AEC-Q101 compliance and SOT323 footprint consistency.
Supply support for BC817W-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 high-volume, high-reliability logic, discrete, and MOSFET devices, with leadership in automotive-qualified components.
The BC817W-Q belongs to Nexperia's AEC-Q101-qualified general-purpose transistor product line, engineered specifically for robust, cost-effective switching and amplification in harsh automotive environments.
FAQ
What is the maximum allowable junction temperature for BC817W-Q?
The absolute maximum junction temperature (Tj) is 150 °C, as specified in Table 6 of the official Nexperia datasheet. Operation beyond this limit risks permanent degradation of hFE and increased leakage currents. Derating is required above 25 °C ambient, with Ptot decreasing linearly to zero at 150 °C junction temperature.
Is BC817W-Q pin-compatible with BC847BW-Q?
Yes - both use identical SOT323 (SC-70) package with base-emitter-collector pinout (1-B, 2-E, 3-C). However, BC817W-Q supports 500 mA continuous current versus BC847BW-Q's 100 mA rating, so direct substitution is electrically unsafe in high-current applications despite mechanical compatibility.
Does BC817W-Q require external base current limiting in switching applications?
Yes - a series base resistor is mandatory to set IB ≥ IC/10 for guaranteed saturation. For 500 mA collector current, minimum IB = 50 mA is required; with typical VBE ≈ 1.2 V at 25 °C, a 180 Ω resistor is needed from a 10 V drive source to achieve this.
How does thermal resistance change with PCB copper area for BC817W-Q?
Rth(j-a) improves from 625 K/W (standard footprint) to 431 K/W when the collector pad is expanded to 1 cm² on FR4 - a 31% reduction. This allows ~30% higher continuous power dissipation at the same ambient temperature, directly enabling sustained 500 mA operation in thermally constrained layouts.
BC817W-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:
- NPN
- Current - Collector (Ic) (Max):
- 500 mA
- Voltage - Collector Emitter Breakdown (Max):
- 45 V
- Vce Saturation (Max) @ Ib, Ic:
- 700mV @ 50mA, 500mA
- Current - Collector Cutoff (Max):
- 100nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 100 @ 100mA, 1V
- 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
BC817W-QX FAQ
1.How can I place an order for BC817W-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817W-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 BC817W-QX reliable?
The price and inventory of BC817W-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817W-QX is usually 5 days.
3.What payment methods are accepted for BC817W-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817W-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817W-QX?
BC817W-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817W-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 BC817W-QX?
For technical support, including BC817W-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817W-QX requirements.
6.How does Aetrix verify that BC817W-QX is sourced from the original manufacturer or authorized distributors?
All BC817W-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 BC817W-QX meets industry standards.
7.What is the process for return or replacement of BC817W-QX?
All BC817W-QX units undergo pre-shipment inspection (PSI). If there is an issue with BC817W-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 BC817W-QX part is unused and in its original packaging.
Return procedure for BC817W-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC817W-QX Tags
-
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
Diodes Incorporated
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BC846BLT1G
onsemi
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BC847B,215
Nexperia USA Inc.
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SMMBT3904LT1G
onsemi
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MMBT2222A-TP
Micro Commercial Co
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MMBTA06LT1G
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MMBT2222ALT1G
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