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Nexperia USA Inc. BC817K-40R
- Part No.:
- BC817K-40R
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BC817K-40R.pdf
- Description:
- TRANS NPN 45V 0.5A TO-236AB
- Quantity:
- Payment:
- Shipping:
Inventory:2,997
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Product details
Overview
BC817K-40R from Nexperia is an AEC-Q101 qualified NPN general-purpose transistor in SOT23 (TO-236AB) package, rated for 45 V VCEO, 500 mA continuous collector current, and DC current gain (hFE) of 250–600 at VCE = 1 V, IC = 100 mA. It serves as a robust switching and amplification device in automotive body control modules, industrial sensor interfaces, and power supply enable circuits.
For engineers reviewing the BC817K-40R datasheet, BC817K-40R pinout, BC817K-40R application, or BC817K-40R equivalent, this page delivers verified electrical parameters, thermal derating behavior, SOT23 terminal mapping, automotive-grade reliability validation, and direct substitution guidance against BC817-40 and BC847C.
Technical Context
This discrete NPN bipolar junction transistor operates in linear or saturated switching modes with base-controlled current amplification. Its hFE range (250–600) enables stable biasing across temperature (−55 °C to 150 °C) and supports low-base-drive designs in 3.3 V/5 V logic interfacing.
Thermal performance is defined by Rth(j-a) values from 162 K/W (4-layer PCB, enhanced pad) to 358 K/W (standard FR4), and safe operating area (SOA) is validated up to 1 A peak pulse (tp ≤ 1 ms) at VCE ≤ 45 V - critical for transient load switching in automotive ECUs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum collector-emitter voltage before breakdown; ensures compatibility with 24 V automotive systems and 36 V industrial rails. |
| IC | 500 mA continuous - Supports medium-power loads such as relays, LEDs, and small solenoids without external heat sinking on standard PCBs. |
| hFE | 250–600 @ VCE=1 V, IC=100 mA - Enables precise current mirror design and low-base-current switching in battery-powered sensors. |
| VCE(sat) | ≤ 700 mV @ IC=500 mA, IB=50 mA - Minimizes conduction loss and self-heating in high-duty-cycle switching applications. |
| Ptot | 775 mW @ Tamb ≤ 25 °C (4-layer PCB, 1 cm² collector pad) - Defines maximum dissipation under optimized layout; derates linearly above 25 °C. |
| fT | 100 MHz @ VCE=5 V, IC=10 mA - Supports signal amplification up to audio frequencies and fast digital edge handling in interface circuits. |
Pinout & Package
SOT23 (TO-236AB) plastic surface-mount package: 3-pin, 1.3 mm × 2.9 mm footprint, 1.1 mm height, tin-plated leads compatible with standard reflow profiles.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Current-controlled input node; requires 50 mA drive for full saturation at 500 mA collector load. |
| 2 | Emitter (E) | Reference node for bias network; connected to ground or low-side return path in common-emitter configurations. |
| 3 | Collector (C) | High-current output node; thermally coupled to PCB copper for power dissipation management. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive underhood environments per stress test requirements - enables use in engine control, lighting, and ADAS subsystems without additional qualification. |
| Three hFE bins (16/25/40) | BC817K-40R provides highest gain bin (250–600), reducing base drive requirements and simplifying driver circuitry in space-constrained layouts. |
| High Ptot capability | 775 mW rating on 4-layer PCB allows >2× power handling vs. legacy BC817 variants - extends usable current range without heatsinking. |
| Low VBE(sat) | ≤ 1.2 V @ IC=500 mA, IB=50 mA - improves noise margin when driven from 3.3 V microcontrollers and reduces base resistor power loss. |
Applications
| Automotive Body Control Unit (BCU) | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Driving 12 V relay coils and LED status indicators in door module ECU. IC Role / Device Role / Timing Role: NPN switch controlling load current with logic-level base drive from MCU GPIO. Use Value: AEC-Q101 qualification ensures long-term reliability under thermal cycling and vibration; 45 V rating accommodates load dump transients. |
Use Scenario: Amplifying low-level analog signals from RTD or thermistor bridges before ADC sampling. IC Role / Device Role / Timing Role: Linear-mode emitter-follower buffer isolating sensor from ADC input impedance. Use Value: Tight hFE tolerance (250–600) and low VBE drift (<±2 mV/°C) maintain gain stability across −40 °C to +125 °C ambient. |
| DC-DC Converter Enable Circuit | Smart Home Power Management |
Use Scenario: Enabling/disabling buck converter ICs via open-collector logic interface. IC Role / Device Role / Timing Role: High-side or low-side level translator between 3.3 V controller and 5–12 V enable rail. Use Value: Fast turn-on (ton < 200 ns typical) and low VCE(sat) minimize enable delay and standby power loss. |
Use Scenario: Controlling AC mains-connected relays and triacs in smart outlet controllers. IC Role / Device Role / Timing Role: Isolated gate driver stage triggered by optocoupler output. Use Value: 1 A peak current rating supports surge currents during relay coil energization; SOT23 footprint saves board space in compact enclosures. |
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 | No AEC-Q101 qualification; identical hFE, VCEO, and IC ratings; same SOT23 package. | Not approved for automotive production; suitable for industrial/commercial designs where qualification is not mandated. | Select when cost sensitivity outweighs automotive compliance; verify lifecycle continuity separately. |
| BC847C | Lower VCEO (45 V same), but hFE = 420–800 @ IC=2 mA; lower IC rating (100 mA); smaller SOT23 variant. | Optimized for low-current signal amplification, not power switching; unsuitable for >200 mA loads. | Choose only for low-power analog stages; avoid for switching loads exceeding 200 mA due to SOA limitations. |
Compared with BC817-40, BC817K-40R adds automotive qualification without sacrificing electrical specs; versus BC847C, it trades higher gain for significantly higher current capacity and ruggedized SOA - making it the preferred choice for automotive and industrial switching.
Availability
BC817K-40R is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, and DC-DC enable circuits requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for BC817K-40R 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-qualified components and advanced packaging.
The BC817K series belongs to Nexperia's AEC-Q101-qualified general-purpose transistor portfolio, engineered specifically for robust switching and amplification in harsh automotive and industrial environments.
FAQ
What is the maximum allowable junction temperature for BC817K-40R?
The absolute maximum junction temperature (Tj) is 150 °C, as defined in the Absolute Maximum Ratings table. Operation beyond this limit risks permanent degradation of hFE and increased leakage. Thermal design must ensure Tj remains ≤150 °C under worst-case ambient and power dissipation conditions, using the appropriate Rth(j-a) value for the PCB construction.
Is BC817K-40R pin-compatible with BC817-40?
Yes - both share identical SOT23 (TO-236AB) package dimensions and pin 1 (base), pin 2 (emitter), pin 3 (collector) assignment. No layout change is required for drop-in replacement; however, BC817K-40R adds AEC-Q101 qualification and may exhibit tighter parametric distributions due to enhanced process controls.
Can BC817K-40R be used in linear amplifier configurations?
Yes - its specified hFE linearity over IC (250–600 at 100 mA), low VBE drift, and fT of 100 MHz support Class-A and emitter-follower amplifier topologies up to ~10 MHz. Avoid operation near VCEO limit or beyond Ptot derating curves to prevent thermal runaway.
What is the marking code for BC817K-40R on the package?
The top-side marking is "HF%", where "%" is a placeholder for the manufacturing site code (e.g., "HFA", "HFB"). This distinguishes it from BC817K-16 ("HD%") and BC817K-25 ("HE%") within the same family and confirms the hFE = 250–600 bin.
BC817K-40R 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:
- 250 mW
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-236AB
BC817K-40R FAQ
1.How can I place an order for BC817K-40R through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817K-40R 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-40R reliable?
The price and inventory of BC817K-40R are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817K-40R is usually 5 days.
3.What payment methods are accepted for BC817K-40R?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817K-40R transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817K-40R?
BC817K-40R orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817K-40R 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-40R?
For technical support, including BC817K-40R datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817K-40R requirements.
6.How does Aetrix verify that BC817K-40R is sourced from the original manufacturer or authorized distributors?
All BC817K-40R 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-40R meets industry standards.
7.What is the process for return or replacement of BC817K-40R?
All BC817K-40R units undergo pre-shipment inspection (PSI). If there is an issue with BC817K-40R, 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-40R part is unused and in its original packaging.
Return procedure for BC817K-40R:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC817K-40R Tags
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