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Nexperia USA Inc. BC817-40QAZ
- Part No.:
- BC817-40QAZ
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- 3-XDFN Exposed Pad
- Datasheet:
-
BC817-40QAZ.pdf
- Description:
- TRANS NPN 45V 0.5A DFN1010D-3
- Quantity:
- Payment:
- Shipping:
Inventory:22,632
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Product details
Overview
BC817-40QAZ from Nexperia is a 45 V, 500 mA NPN general-purpose transistor in an AEC-Q101 qualified DFN1010D-3 (SOT1215) package with 0.37 mm height, used for low-profile switching and amplification in automotive and mobile power stages.
For engineers reviewing the BC817-40QAZ datasheet, BC817-40QAZ pinout, BC817-40QAZ application, or BC817-40QAZ equivalent, key selection criteria include DC current gain (250–600 at IC = 100 mA), VCE(sat) ≤ 700 mV at IC = 500 mA/IB = 50 mA, thermal resistance down to 139 K/W (4-layer PCB, 1 cm² collector pad), and automotive-grade reliability per AEC-Q101.
Technical Context
This discrete NPN bipolar junction transistor operates as a current-controlled switch or linear amplifier with base-emitter forward voltage ≤ 1.2 V at IC = 500 mA and transition frequency fT = 100 MHz at VCE = 5 V, IC = 10 mA. Its dual-collector-pin configuration (pins 3 and 4) supports enhanced thermal dissipation in ultra-thin layouts.
The device features two defined current gain bins (BC817-25QA vs. BC817-40QA), with BC817-40QAZ specifying hFE = 250–600 under VCE = 1 V, IC = 100 mA. It meets AEC-Q101 stress test requirements for automotive discrete semiconductors, including temperature cycling, HTRB, and ESD robustness.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage before breakdown; enables use in 24 V automotive supply rails with margin. |
| IC | 500 mA continuous - Sustains typical load currents for LED drivers, relay coils, and small-signal logic-level switching. |
| hFE | 250–600 at VCE = 1 V, IC = 100 mA - High and tightly binned DC gain ensures predictable base drive sizing across production lots. |
| VCE(sat) | ≤ 700 mV at IC = 500 mA, IB = 50 mA - Low saturation voltage minimizes conduction loss and self-heating in switching applications. |
| Ptot | 900 mW with 4-layer PCB + 1 cm² collector pad - Enables higher power handling than standard SOT-23 equivalents in space-constrained designs. |
| Rth(j-a) | 139 K/W (4-layer PCB, 1 cm² pad) - Thermal resistance optimized for compact automotive modules requiring reliable junction temperature control. |
Pinout & Package
DFN1010D-3 (SOT1215) is a leadless, ultra-thin surface-mount package measuring 1.1 × 1.0 × 0.37 mm with visible and solderable side pads for automated optical inspection and reflow compatibility.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base | Control input node; requires current-limited drive (IB ≤ 50 mA typical for full saturation). |
| 2 | Emitter | Reference terminal for current flow; tied to ground or low-side return path in common-emitter configurations. |
| 3 | Collector | Main output current path; electrically connected to pin 4 for parallel routing and improved thermal spreading. |
| 4 | Collector | Redundant collector terminal; shares internal connection with pin 3 to reduce trace inductance and enhance heat transfer to PCB copper. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive underhood and infotainment applications, including temperature cycling (−55 °C to +150 °C) and HTRB testing. |
| Ultra-low profile (0.37 mm) | Enables integration into slim mobile devices and stacked PCB assemblies where Z-height is constrained below 0.4 mm. |
| Dual collector terminals | Provides redundant current paths and lowers effective thermal resistance by enabling symmetric copper pour attachment on both sides of the package. |
| High hFE bin (250–600) | Reduces required base drive current by up to 2× versus BC817-25 variants, easing MCU GPIO loading and reducing driver component count. |
Applications
| Automotive Interior Lighting | Mobile Power Management |
|---|---|
|
Use Scenario: Driving white LED strings in dashboard backlighting and ambient lighting modules. IC Role / Device Role / Timing Role: NPN switch controlling LED current via PWM dimming at 1–10 kHz. Use Value: Low VCE(sat) (≤700 mV) minimizes power loss and thermal rise in sealed enclosures; AEC-Q101 ensures 15-year field reliability. |
Use Scenario: Enabling/disabling USB peripheral power rails in smartphones and wearables. IC Role / Device Role / Timing Role: Low-side load switch activated by application processor GPIO. Use Value: 0.37 mm height allows placement beneath battery connectors; high hFE reduces base current demand, extending battery life. |
| Industrial Sensor Interface | Consumer Audio Amplifier Stage |
|
Use Scenario: Level-shifting and buffering analog sensor outputs (e.g., thermistors, Hall sensors) to ADC inputs. IC Role / Device Role / Timing Role: Common-emitter amplifier with fixed bias network for signal conditioning. Use Value: Tight hFE bin (250–600) ensures consistent gain across units; low Cc (3 pF) preserves bandwidth up to 100 MHz. |
Use Scenario: Output stage in Class-A headphone amplifiers for portable audio players. IC Role / Device Role / Timing Role: Linear amplification element biased in active region for low-distortion signal reproduction. Use Value: fT = 100 MHz supports full audio bandwidth with headroom; low VBE (≤1.2 V) simplifies bias network design. |
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 |
|---|---|---|---|
| BC817-40,115 (SOT-23) | Same electrical specs but in larger SOT-23 package (1.3 × 2.9 × 1.1 mm); Rth(j-a) = 350 K/W (standard footprint). | Not suitable for ultra-thin or high-density layouts; preferred where manual rework or thermal margin >200 K/W is acceptable. | Select when board assembly lacks fine-pitch reflow capability or when legacy footprint compatibility is required. |
| MMBT3904LT1G | Lower VCEO (40 V), lower hFE (100–300), no AEC-Q101 qualification; TO-236AB (SOT-23) package. | Limited to non-automotive consumer applications; unsuitable for 24 V systems or temperature-cycled environments. | Choose only for cost-sensitive, non-automotive designs where 45 V rating and AEC-Q101 are not required. |
Compared with BC817-40,115, BC817-40QAZ delivers 2.5× better thermal performance in dense layouts; versus MMBT3904LT1G, it adds automotive qualification, higher voltage margin, and tighter hFE binning-critical for deterministic base drive in safety-relevant subsystems.
Availability
BC817-40QAZ is available at Aetrix Electronics and suitable for automotive interior lighting, mobile power management, industrial sensor interface, and consumer audio amplifier stages requiring stable component supply and AEC-Q101 compliance.
Supply support for BC817-40QAZ 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 and logic devices for automotive, industrial, and mobile markets.
BC817-40QAZ belongs to Nexperia's AEC-Q101-qualified general-purpose transistor family, engineered for space-constrained, thermally demanding applications where reliability, low profile, and precise gain binning are critical.
FAQ
Is BC817-40QAZ pin-compatible with standard SOT-23 NPN transistors?
No. BC817-40QAZ uses the DFN1010D-3 (SOT1215) 4-pin leadless package with pins 1–2–3–4 assigned as Base–Emitter–Collector–Collector. It is not physically or electrically pin-compatible with 3-pin SOT-23 devices like BC817-40,115 or MMBT3904LT1G due to different footprint, terminal count, and dual-collector topology.
What is the maximum allowable PCB copper area for optimal thermal performance?
With a 1 cm² tin-plated copper pad connected to both collector terminals (pins 3 and 4) on a 4-layer FR4 PCB, Rth(j-a) reaches 139 K/W and Ptot rises to 900 mW. Larger copper areas yield diminishing returns; verified thermal data confirms no further improvement beyond 1 cm² under standard JEDEC test conditions.
Does BC817-40QAZ support pulsed operation beyond its DC ratings?
Yes. The datasheet specifies ICM = 1 A for single pulses ≤1 ms and IBM = 200 mA under identical conditions. Pulse operation must respect the transient thermal impedance curves (Fig 4–6) and maintain duty cycle δ ≤ 0.02 for tp ≤ 300 μs to avoid junction overheating.
How does the AEC-Q101 qualification impact manufacturing and testing?
AEC-Q101 qualification requires 100% wafer-level and final-test screening per stress test standards-including HTGB, HTRB, temperature cycling, and ESD (HBM ≥ 8 kV). All BC817-40QAZ units undergo this extended test flow, ensuring failure-in-time (FIT) rates <100 ppm and guaranteed operation from −55 °C to +150 °C junction temperature.
BC817-40QAZ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- 3-XDFN Exposed Pad
- 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:
- 40 @ 500mA, 1V
- Power - Max:
- 900 mW
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DFN1010D-3
BC817-40QAZ FAQ
1.How can I place an order for BC817-40QAZ through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817-40QAZ 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 BC817-40QAZ reliable?
The price and inventory of BC817-40QAZ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817-40QAZ is usually 5 days.
3.What payment methods are accepted for BC817-40QAZ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817-40QAZ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817-40QAZ?
BC817-40QAZ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817-40QAZ 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 BC817-40QAZ?
For technical support, including BC817-40QAZ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817-40QAZ requirements.
6.How does Aetrix verify that BC817-40QAZ is sourced from the original manufacturer or authorized distributors?
All BC817-40QAZ 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 BC817-40QAZ meets industry standards.
7.What is the process for return or replacement of BC817-40QAZ?
All BC817-40QAZ units undergo pre-shipment inspection (PSI). If there is an issue with BC817-40QAZ, 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 BC817-40QAZ part is unused and in its original packaging.
Return procedure for BC817-40QAZ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC817-40QAZ Tags
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