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Nexperia USA Inc. BC817-25W-QX
- Part No.:
- BC817-25W-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- SC-70, SOT-323
- Datasheet:
-
BC817-25W-QX.pdf
- Description:
- TRANS NPN 45V 0.5A SOT-323
- Quantity:
- Payment:
- Shipping:
Inventory:4,470
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Product details
Overview
BC817-25W-Q from Nexperia is a 45 V, 500 mA NPN general-purpose transistor in SOT323 (SC-70) package, designed for low-voltage switching and linear amplification in space-constrained automotive and industrial PCBs. It delivers hFE of 160–400 at VCE = 1 V, IC = 100 mA, supports 1 A peak collector current, and is qualified to AEC-Q101.
For engineers reviewing the BC817-25W-Q datasheet, BC817-25W-Q pinout, BC817-25W-Q application, or BC817-25W-Q equivalent, this page provides verified electrical parameters, thermal derating curves, automotive qualification status, and real-world use cases for discrete BJT selection in cost-sensitive, high-reliability designs.
Technical Context
This NPN bipolar junction transistor operates with open-base collector-emitter breakdown voltage of 45 V and emitter-base breakdown voltage of 5 V, enabling safe use in 24 V automotive supply rails and 5 V logic-level control interfaces. Its pulsed hFE range (160–400) ensures stable DC gain across temperature and current variations.
The device exhibits VCE(sat) ≤ 700 mV at IC = 500 mA / IB = 50 mA and VBE ≤ 1.2 V under same conditions, supporting efficient saturation in low-side switch configurations. Thermal resistance Rth(j-a) is 431 K/W with 1 cm² collector pad, enabling reliable operation up to 150 °C junction temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage with base open; enables use in 24 V automotive systems with margin. |
| IC | 500 mA continuous - Supports medium-power load switching such as LED drivers, relay coils, and sensor interface stages. |
| hFE | 160–400 at VCE = 1 V, IC = 100 mA - Tighter gain band than BC817-16W-Q, improving bias stability in amplifier and feedback circuits. |
| VCE(sat) | ≤ 700 mV at IC = 500 mA, IB = 50 mA - Low saturation voltage reduces conduction loss and self-heating in switching applications. |
| Ptot | 290 mW with 1 cm² copper pad - Higher power dissipation than standard footprint (200 mW), allowing higher duty-cycle operation on optimized layouts. |
| fT | 100 MHz - Sufficient for audio-frequency amplification and PWM signal buffering up to ~10 MHz practical bandwidth. |
| Cc | 3 pF - Low collector capacitance minimizes Miller effect, supporting faster turn-off in digital switching. |
Pinout & Package
SOT323 (SC-70) plastic surface-mounted package: ultra-compact 3-lead outline with 0.65 mm lead pitch, 1.3 mm × 1.8 mm body, and 0.45 mm max height - optimized for high-density PCB assembly and reflow compatibility.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Current-controlled input node; requires ≥13 mA base drive for full 500 mA collector conduction (IC/IB = 38 typical). |
| 2 | Emitter (E) | Reference terminal for bias network; connected to ground or low-impedance return path in common-emitter configurations. |
| 3 | Collector (C) | High-current output node; thermally coupled to PCB copper pad to sustain 290 mW dissipation at Tamb ≤ 25 °C. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Stress-tested per automotive discrete semiconductor standard - validated for under-hood temperature cycling, humidity, and mechanical shock. |
| Three hFE grades | BC817-25W-Q's 160–400 range bridges performance between BC817-16W-Q (100–250) and BC817-40W-Q (250–600), enabling precise gain matching. |
| Low VCE(sat) | 700 mV max at rated current - reduces power loss by >30% vs. legacy general-purpose transistors like BC847, improving thermal headroom. |
| Thermal robustness | Rth(j-a) = 431 K/W with enhanced pad - allows sustained 350 mW operation at 50 °C ambient when layout-optimized, extending lifetime in sealed enclosures. |
| SC-70 footprint | Compatible with JEDEC-standard reflow profiles and wave soldering - eliminates need for custom stencil apertures or placement offsets. |
Applications
| Automotive Interior Lighting | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Driving 12 V LED strips in door modules and dashboard backlighting with PWM dimming. IC Role / Device Role / Timing Role: Low-side switch controlling LED current path; handles 350 mA average load with 1 kHz PWM. Use Value: VCE(sat) ≤ 700 mV limits power loss to <125 mW, preventing thermal runaway in confined plastic housings. |
Use Scenario: Amplifying millivolt-level output from RTD or thermistor bridges in PLC analog input modules. IC Role / Device Role / Timing Role: NPN emitter-follower buffer isolating sensitive bridge from ADC input impedance. Use Value: hFE ≥ 160 ensures minimal loading error (<0.5%) across –40 °C to +125 °C operating range. |
| Consumer Appliance Motor Control | Medical Diagnostic Equipment Power Sequencing |
Use Scenario: Switching 24 V brushed DC fan motors in HVAC controllers and coffee makers. IC Role / Device Role / Timing Role: Saturated switch interfacing microcontroller GPIO to motor driver stage; handles 500 mA stall current. Use Value: 45 V VCEO accommodates inductive kickback spikes without clamping diodes in cost-sensitive designs. |
Use Scenario: Enabling regulated power rails in portable ultrasound units using discrete enable logic. IC Role / Device Role / Timing Role: High-reliability level-shifter translating 1.8 V FPGA control signals to 5 V/12 V power MOSFET gates. Use Value: AEC-Q101 qualification ensures zero infant mortality in field-deployed devices requiring 10+ year service life. |
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 |
|---|---|---|---|
| BC817-25LT1G | Same hFE band (160–400) but SOT23 package; Rth(j-a) = 400 K/W (standard footprint); no AEC-Q101 qualification. | Preferred for non-automotive consumer boards where footprint compatibility with legacy SOT23 is required. | Select when AEC-Q101 is not mandated and board space allows larger SOT23; avoid in automotive or high-temp industrial use. |
| MMBT3904-7-F | Lower VCEO (40 V), wider hFE (100–300), unqualified for automotive; 300 mW Ptot with standard SOT23. | Suitable for 5 V/12 V logic-level switching only; insufficient margin for 24 V automotive transients. | Choose only for cost-driven 5 V embedded systems; verify transient immunity separately if used near inductive loads. |
Compared with BC817-25LT1G and MMBT3904-7-F, BC817-25W-Q uniquely combines AEC-Q101 qualification, SC-70 miniaturization, and 45 V breakdown - making it the sole option for space-constrained automotive signal switching where reliability and size are co-prioritized.
Availability
BC817-25W-Q is available at Aetrix Electronics and suitable for automotive interior lighting, industrial sensor conditioning, consumer appliance motor control, and medical diagnostic equipment requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for BC817-25W-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 essential semiconductors - delivering discrete, logic, and MOSFET solutions for automotive, industrial, and mobile markets.
The BC817W-Q series targets cost-sensitive, space-constrained applications demanding AEC-Q101 compliance and consistent parametric performance - especially in automotive body electronics and industrial control subsystems.
FAQ
What is the maximum allowable junction temperature for BC817-25W-Q?
The absolute maximum junction temperature is 150 °C, as defined in Table 6 of the datasheet. Operation above this limit risks permanent degradation of hFE and increased leakage. Derating begins at 25 °C ambient when using the 1 cm² copper pad layout, with linear reduction to zero power at 150 °C.
Does BC817-25W-Q require a base resistor in switching applications?
Yes - a current-limiting base resistor is mandatory to set IB ≥ IC/hFE(min). For 500 mA collector current and minimum hFE of 160, IB must be ≥ 3.125 mA. With 3.3 V GPIO driving the base, a 1 kΩ resistor yields ~2.6 mA after VBE drop, so 820 Ω is recommended for guaranteed saturation.
How does the SOT323 package affect thermal performance versus SOT23?
SOT323 has smaller pad area and thinner mold compound than SOT23, resulting in higher Rth(j-a) (431 K/W vs. ~400 K/W for SOT23 with same pad). However, its lower thermal mass enables faster transient response, and the standardized SC-70 footprint allows tighter layout spacing - critical for multi-channel sensor front-ends.
Can BC817-25W-Q replace BC817-25 in existing designs?
No direct drop-in replacement: BC817-25 uses TO-92 through-hole packaging while BC817-25W-Q is SOT323 surface-mount. Layout redesign is required. Electrically, both share identical hFE, VCEO, and IC ratings, but thermal behavior differs significantly due to package construction and PCB coupling.
BC817-25W-QX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BC817W-Q
- 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:
- 160 @ 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
BC817-25W-QX FAQ
1.How can I place an order for BC817-25W-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817-25W-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 BC817-25W-QX reliable?
The price and inventory of BC817-25W-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817-25W-QX is usually 5 days.
3.What payment methods are accepted for BC817-25W-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817-25W-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817-25W-QX?
BC817-25W-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817-25W-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 BC817-25W-QX?
For technical support, including BC817-25W-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817-25W-QX requirements.
6.How does Aetrix verify that BC817-25W-QX is sourced from the original manufacturer or authorized distributors?
All BC817-25W-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 BC817-25W-QX meets industry standards.
7.What is the process for return or replacement of BC817-25W-QX?
All BC817-25W-QX units undergo pre-shipment inspection (PSI). If there is an issue with BC817-25W-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 BC817-25W-QX part is unused and in its original packaging.
Return procedure for BC817-25W-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC817-25W-QX Tags
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MMBT3904LT1G
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MMBT3906-7-F
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BC846BLT1G
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