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Nexperia USA Inc. BC817K-40HVL
- Part No.:
- BC817K-40HVL
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BC817K-40HVL.pdf
- Description:
- TRANS NPN 45V 0.5A TO-236AB
- Quantity:
- Payment:
- Shipping:
Inventory:34,985
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Product details
Overview
BC817K-40HVL from Nexperia is a 45 V, 500 mA NPN general-purpose transistor in SOT23 package, optimized for switching and linear amplification in industrial control logic, power supply feedback paths, and LED driver stages. It delivers hFE = 250–600 at VCE = 1 V, IC = 100 mA, operates up to 175 °C junction temperature, and supports peak collector current of 1 A.
For engineers reviewing the BC817K-40HVL datasheet, BC817K-40HVL pinout, BC817K-40HVL application, or BC817K-40HVL equivalent, this page provides verified electrical parameters, thermal derating curves, SOT23 footprint details, and validated alternatives for high-reliability discrete BJT selection in cost-sensitive, thermally demanding designs.
Technical Context
This NPN bipolar junction transistor uses epitaxial planar technology with a robust base-emitter junction rated for 7 V reverse voltage and collector-base breakdown of 50 V. Its DC current gain (hFE) is binned to 250–600 at 100 mA collector current, enabling predictable biasing in low-to-medium-speed switching circuits.
The device exhibits VCE(sat) ≤ 700 mV at IC = 500 mA / IB = 50 mA and fT ≥ 100 MHz at VCE = 5 V, IC = 10 mA - confirming suitability for audio preamplifiers, relay drivers, and PWM-controlled load interfaces up to several hundred kHz.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage with open base; defines upper rail limit in switch-mode applications. |
| IC | 500 mA continuous - Sustained current handling capability under 25 °C ambient with standard PCB mounting. |
| hFE | 250–600 at VCE = 1 V, IC = 100 mA - Enables stable DC bias design with minimal base drive variation across production lots. |
| VCE(sat) | ≤ 700 mV at IC = 500 mA, IB = 50 mA - Ensures low conduction loss and minimal self-heating in saturated switch operation. |
| Tj(max) | 175 °C - Supports operation in high-temperature environments such as motor control enclosures or automotive under-hood modules. |
| Ptot | 950 mW on 4-layer FR4 PCB with 1 cm² collector pad - Defines maximum power dissipation before thermal shutdown or degradation. |
| fT | ≥ 100 MHz - Confirms usable bandwidth for signal amplification up to mid-audio frequencies and fast digital edge shaping. |
Pinout & Package
SOT23 (TO-236AB) plastic surface-mounted package with 3 leads; 1.9 mm × 1.1 mm body, 0.45 mm nominal thickness, and gull-wing lead form compatible with standard reflow soldering profiles.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Current-controlled input node; requires series resistor to limit IB ≤ 200 mA peak and ensure saturation at target IC. |
| 2 | Emitter (E) | Reference terminal for bias network; connects to ground or low-side return path in common-emitter configurations. |
| 3 | Collector (C) | High-current output node; routed to load or pull-up rail; thermal performance depends on copper area connected to this pad. |
Key Features
| Feature | Design Value |
|---|---|
| Three hFE bins | BC817K-40H offers 250–600 gain range - simplifies circuit tuning without custom bias resistors across production batches. |
| High-temperature operation | Rated for Tj up to 175 °C - eliminates derating concerns in sealed enclosures or near heat-generating components. |
| Low VCE(sat) | ≤ 700 mV at full 500 mA load - reduces power loss by >30% versus legacy general-purpose transistors like BC547. |
| Robust ESD rating | HBM ≥ 8 kV - withstands typical handling and board assembly electrostatic events without parameter shift or failure. |
| Standard SOT23 footprint | Compatible with IPC-7351B SOIC-3 land pattern - enables drop-in replacement and automated optical inspection (AOI) compatibility. |
Applications
| Industrial Relay Driver | DC-DC Feedback Transistor |
|---|---|
Use Scenario: Driving 12 V/50 mA coil relays in programmable logic controllers (PLCs) with microcontroller GPIO outputs. IC Role / Device Role / Timing Role: NPN switch in common-emitter configuration, turning relay ON/OFF via base current control. Use Value: Low VCE(sat) minimizes coil voltage drop, ensuring reliable relay pull-in even at 3.3 V MCU logic levels with 10 kΩ base resistor. |
Use Scenario: Error amplifier stage in isolated flyback converters, comparing optocoupler feedback signal to reference voltage. IC Role / Device Role / Timing Role: Linear amplifier modulating optocoupler LED current to regulate secondary-side output voltage. Use Value: Tight hFE bin (250–600) ensures consistent loop gain across temperature, improving output regulation accuracy to ±2%. |
| LED Current Switch | Microcontroller Interface Buffer |
Use Scenario: Controlling 24 V, 350 mA indicator LEDs in HMI panels where MCU I/O cannot source sufficient current. IC Role / Device Role / Timing Role: High-side or low-side current switch, dissipating <150 mW at full load with proper heatsinking. Use Value: 175 °C max junction temperature allows direct mounting on metal chassis without thermal pads, reducing BOM count. |
Use Scenario: Level-shifting and current boosting between 3.3 V ARM Cortex-M peripherals and 5 V legacy sensors or displays. IC Role / Device Role / Timing Role: Digital buffer providing 5 V logic-compatible output while isolating MCU pins from bus capacitance. Use Value: fT ≥ 100 MHz supports clean 10 MHz SPI clock edges, preventing setup/hold violations in high-speed sensor interfaces. |
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 |
|---|---|---|---|
| BC817-40W | Same hFE range (250–600), but SOT323 package (smaller footprint, lower Ptot = 300 mW). | Not suitable for >200 mA continuous loads due to thermal limits; best for space-constrained signal-level switching. | Select when PCB area is critical and power dissipation remains below 150 mW. |
| MMBT4401 | Higher VCEO = 40 V (vs. 45 V), hFE = 100–300 (narrower bin), VCE(sat) = 750 mV at same conditions. | Marginally lower gain consistency and higher saturation voltage reduce efficiency in high-duty-cycle switching. | Choose only if existing design uses MMBT4401 and minor performance trade-offs are acceptable. |
Compared with BC817K-40HVL, BC817-40W sacrifices thermal headroom for miniaturization, while MMBT4401 trades gain stability and saturation performance for broader second-source availability - making BC817K-40HVL optimal for thermally demanding, precision-biased applications.
Availability
BC817K-40HVL is available at Aetrix Electronics and suitable for industrial automation, power supply feedback loops, and LED lighting systems requiring stable component supply across extended temperature ranges and multi-year production cycles.
Supply support for BC817K-40HVL 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 discrete and logic devices, with leadership in automotive-grade and industrial-standard components.
The BC817KH series targets cost-sensitive, thermally robust general-purpose switching and amplification - designed specifically for applications needing guaranteed hFE bins, extended temperature operation, and SOT23 manufacturability.
FAQ
What is the maximum allowable base current for BC817K-40HVL?
The absolute maximum peak base current is 200 mA per datasheet limiting values (Table 6). For continuous operation, base current must be limited to maintain junction temperature ≤175 °C - typically ≤50 mA at IC = 500 mA with adequate PCB copper area. Exceeding 200 mA pulse risks permanent bond wire damage.
Does BC817K-40HVL support automotive qualification?
No. Per Revision History (Section 13), BC817KH_SER v.2 explicitly states product status changed to non-automotive qualification in 2025. Automotive-grade equivalents (e.g., BC817-40Q) are separately qualified and marked with "-Q" suffix - BC817K-40HVL is intended for industrial, consumer, and computing applications only.
How does thermal resistance vary with PCB layout?
Rth(j-a) ranges from 158 K/W (4-layer FR4, 1 cm² collector pad) to 353 K/W (single-sided FR4, standard footprint). A 1 cm² copper pour under the collector pad reduces thermal resistance by >55%, directly lowering junction temperature rise by ~110 °C at 500 mW dissipation - critical for sustained high-current operation.
Can BC817K-40HVL replace BC817-40 in existing designs?
Yes, with verification. Both share identical SOT23 pinout and electrical specs, but BC817K-40HVL features tighter hFE binning (250–600 vs. 100–630 for BC817-40) and improved thermal specs. Confirm base resistor values remain appropriate for the higher minimum hFE, and validate thermal margin using the updated Rth(j-a) curves in Figure 1.
BC817K-40HVL Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- 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:
- 250 @ 100mA, 1V
- Power - Max:
- 350 mW
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-236AB
BC817K-40HVL FAQ
1.How can I place an order for BC817K-40HVL through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817K-40HVL 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 BC817K-40HVL reliable?
The price and inventory of BC817K-40HVL are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817K-40HVL is usually 5 days.
3.What payment methods are accepted for BC817K-40HVL?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817K-40HVL transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817K-40HVL?
BC817K-40HVL orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817K-40HVL 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 BC817K-40HVL?
For technical support, including BC817K-40HVL datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817K-40HVL requirements.
6.How does Aetrix verify that BC817K-40HVL is sourced from the original manufacturer or authorized distributors?
All BC817K-40HVL 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 BC817K-40HVL meets industry standards.
7.What is the process for return or replacement of BC817K-40HVL?
All BC817K-40HVL units undergo pre-shipment inspection (PSI). If there is an issue with BC817K-40HVL, 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 BC817K-40HVL part is unused and in its original packaging.
Return procedure for BC817K-40HVL:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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