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Nexperia USA Inc. BC817K-25HR
- Part No.:
- BC817K-25HR
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BC817K-25HR.pdf
- Description:
- TRANS NPN 45V 0.5A TO-236AB
- Quantity:
- Payment:
- Shipping:
Inventory:1,180
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Product details
Overview
BC817K-25HR 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 loops, and LED driver stages. It delivers hFE = 160–400 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-25HR datasheet, BC817K-25HR pinout, BC817K-25HR application, or BC817K-25HR equivalent, this page provides verified electrical parameters, thermal derating curves, safe operating area (SOA) boundaries, and validated alternatives for discrete BJT selection in cost-sensitive, high-reliability embedded systems.
Technical Context
This device implements a planar epitaxial silicon NPN structure with optimized base doping and emitter geometry to achieve stable DC current gain across wide temperature (−55 °C to +175 °C) and collector current (10 mA to 500 mA) ranges. Its low VCE(sat) ≤ 700 mV at IC = 500 mA / IB = 50 mA enables efficient low-voltage switching in 3.3 V and 5 V logic interfaces.
The SOT23 package provides standardized surface-mount compatibility with FR4 PCBs, supporting multiple thermal mounting configurations-standard footprint, 1 cm² collector pad, and 4-layer copper-to deliver Rth(j-a) from 158 K/W to 353 K/W depending on layout. Transient thermal impedance data confirms robust pulsed operation under short-duration loads.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum collector-emitter voltage before breakdown; defines safe operating headroom in 24 V and 36 V supply rails. |
| IC | 500 mA continuous - Rated collector current at Tamb = 25 °C; supports medium-power load switching without forced cooling. |
| hFE | 160–400 at VCE = 1 V, IC = 100 mA - Tight DC current gain bin ensures predictable base drive requirements in amplifier and switch designs. |
| VCE(sat) | ≤ 700 mV at IC = 500 mA, IB = 50 mA - Low saturation voltage minimizes conduction loss and self-heating in saturated-switch applications. |
| Tj(max) | 175 °C - Maximum junction temperature rating enables reliable operation in high-ambient environments such as motor drives and automotive under-hood modules. |
| fT | 100 MHz at VCE = 5 V, IC = 10 mA - Transition frequency supports audio-frequency amplification and fast digital switching up to ~10 MHz. |
| Cc | 3 pF at VCB = 10 V - Low collector capacitance reduces Miller effect and improves high-frequency stability in common-emitter configurations. |
Pinout & Package
SOT23 (TO-236AB) plastic surface-mounted package with 3 leads; dimensions per Figure 43: 2.9 mm × 1.3 mm × 1.0 mm (L × W × H), 0.95 mm lead pitch, standard JEDEC-compliant footprint.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Control terminal for forward-biased injection; requires current-limited drive (e.g., 5–50 mA) to ensure full saturation without overdrive stress. |
| 2 | Emitter (E) | Current return path; connected to ground or low-side reference; must be routed with low-inductance trace in high-speed switching. |
| 3 | Collector (C) | Output current path; thermally coupled to PCB copper; mounting pad size directly impacts power dissipation capability and thermal resistance. |
Key Features
| Feature | Design Value |
|---|---|
| Three hFE bins | BC817K-16H (100–250), BC817K-25H (160–400), BC817K-40H (250–600) - Enables precise gain matching for analog circuits and consistent switching thresholds across production batches. |
| High-temperature operation | Rated to 175 °C junction temperature - Supports deployment in industrial motor controllers, power converters, and automotive non-safety-critical modules. |
| Low VBE(sat) | ≤ 1.2 V at IC = 500 mA, IB = 50 mA - Reduces base drive power and simplifies bias network design in microcontroller-driven switch stages. |
| Robust SOA | DC and pulsed safe operating area defined up to 1 A/45 V - Validates reliability under inductive load turn-off and transient overload conditions. |
| Standardized SOT23 footprint | JEDEC TO-236AB compliant - Ensures drop-in replacement compatibility with existing pick-and-place equipment and reflow profiles. |
Applications
| Industrial PLC Output Stage | DC-DC Converter Feedback |
|---|---|
|
Use Scenario: Driving 24 V solenoid valves and relay coils in programmable logic controller output modules. IC Role / Device Role / Timing Role: Medium-current NPN switch controlling load current up to 400 mA with TTL/CMOS-compatible base drive. Use Value: Stable hFE binning ensures consistent turn-on behavior across temperature, reducing need for adaptive base resistor tuning in field-deployed units. |
Use Scenario: Error amplifier stage in isolated flyback or forward converter feedback loop using optocoupler interface. IC Role / Device Role / Timing Role: Linear-mode NPN transistor amplifying error signal between reference and sensed output voltage. Use Value: Low VCE(sat) and tight hFE tolerance maintain accurate regulation across line/load transients and ambient variations. |
| LED Driver for Status Indication | Microcontroller GPIO Expander |
|
Use Scenario: Constant-current LED driver for panel indicators in medical and test equipment requiring long-term luminance stability. IC Role / Device Role / Timing Role: Switching element in current-regulated topology with emitter resistor sensing and base driven by MCU PWM. Use Value: 175 °C rating allows placement near heat-generating components without derating, improving board-level thermal management flexibility. |
Use Scenario: Level-shifting and current-boosting interface between 3.3 V microcontroller GPIO and 5 V peripheral logic inputs. IC Role / Device Role / Timing Role: Digital inverter/buffer providing >10 mA sink capability while maintaining logic-level compatibility. Use Value: Verified SOA and low Cc ensure clean edge transitions and immunity to ringing during fast GPIO toggling. |
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 |
|---|---|---|---|
| BC817-25,115 (Nexperia) | Same hFE range (160–400), identical SOT23 package, but marked as non-automotive qualified per Rev. 2 datasheet. | No automotive qualification; suitable for industrial, consumer, and computing applications only. | Select when automotive AEC-Q101 compliance is not required and cost optimization is prioritized. |
| MMBT3904LT1G (onsemi) | Lower VCEO = 40 V, hFE = 100–300, higher VCE(sat) = 0.2 V typical at IC/IB = 10 mA/1 mA. | Not rated for 175 °C operation; max Tj = 150 °C; less suitable for high-temp industrial environments. | Choose for lower-cost, lower-power applications where 40 V headroom and 150 °C operation suffice. |
Compared with BC817K-25HR, BC817-25,115 offers identical electrical performance at lower qualification cost, while MMBT3904LT1G trades off voltage margin and thermal capability for broader distribution and legacy design reuse.
Availability
BC817K-25HR is available at Aetrix Electronics and suitable for industrial PLC output stages, DC-DC converter feedback circuits, LED status drivers, and microcontroller GPIO expansion requiring stable component supply and long-term manufacturability.
Supply support for BC817K-25HR 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, high-reliability discrete and logic devices for automotive, industrial, and consumer markets.
The BC817KH series belongs to Nexperia's general-purpose bipolar transistor product line, engineered for robustness in cost-sensitive, high-volume applications demanding consistent gain, thermal resilience, and standardized SMT packaging.
FAQ
What is the maximum allowable base current for continuous operation?
The absolute maximum peak base current is 200 mA per datasheet Table 6, but continuous operation is limited by thermal constraints. At Tamb = 25 °C with standard SOT23 mounting, sustained IB > 50 mA risks exceeding Ptot = 425 mW (single-sided FR4). For reliable 24/7 operation, keep IB ≤ 30 mA with adequate PCB copper area.
Does BC817K-25HR support automotive applications?
No. Per Revision 2 (2025-09-30), BC817K-25HR is explicitly designated as non-automotive qualified. Nexperia offers automotive-grade alternatives such as BC817-25Q (AEC-Q101 qualified) for safety-critical or under-hood use cases requiring extended temperature validation and PPAP documentation.
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) per Table 7. Using a dedicated 1 cm² copper pour under the collector pin reduces junction-to-ambient thermal resistance by up to 55 %, enabling 2× higher continuous power dissipation at the same ambient temperature.
Can BC817K-25HR replace BC847B in existing designs?
Only with verification. BC847B has VCEO = 45 V and hFE = 200–450, but its SOT23 pinout differs (E-C-B vs. E-B-C). BC817K-25HR uses standard SOT23 pinout (E-B-C), so direct substitution requires PCB trace modification. Electrical compatibility exists, but mechanical fit is not guaranteed without layout review.
BC817K-25HR 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:
- 160 @ 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-25HR FAQ
1.How can I place an order for BC817K-25HR through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817K-25HR 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-25HR reliable?
The price and inventory of BC817K-25HR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817K-25HR is usually 5 days.
3.What payment methods are accepted for BC817K-25HR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817K-25HR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817K-25HR?
BC817K-25HR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817K-25HR 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-25HR?
For technical support, including BC817K-25HR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817K-25HR requirements.
6.How does Aetrix verify that BC817K-25HR is sourced from the original manufacturer or authorized distributors?
All BC817K-25HR 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-25HR meets industry standards.
7.What is the process for return or replacement of BC817K-25HR?
All BC817K-25HR units undergo pre-shipment inspection (PSI). If there is an issue with BC817K-25HR, 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-25HR part is unused and in its original packaging.
Return procedure for BC817K-25HR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC817K-25HR 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
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