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Nexperia USA Inc. BC817-40W/ZLF
- Part No.:
- BC817-40W/ZLF
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- SC-70, SOT-323
- Datasheet:
-
BC817-40W/ZLF.pdf
- Description:
- TRANS PNP 45V SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:8,792
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Product details
Overview
BC817-40W/ZLF from Nexperia is a 45 V, 500 mA NPN general-purpose transistor in SOT323 (SC-70) package, optimized for low-power switching and linear amplification with hFE = 250–600 at VCE = 1 V, IC = 100 mA, and Tamb = 25 °C. It delivers reliable performance in space-constrained consumer and industrial PCBs where thermal efficiency and consistent DC gain are critical.
For engineers reviewing the BC817-40W/ZLF datasheet, BC817-40W/ZLF pinout, BC817-40W/ZLF application, or BC817-40W/ZLF equivalent, this page provides verified package mapping, validated pin functions, confirmed thermal derating curves, and real-world selection guidance against functionally matched alternatives.
Technical Context
This discrete NPN bipolar junction transistor operates in active, saturation, and cutoff regions with defined absolute maximum ratings: VCEO = 45 V, IC = 500 mA, Ptot = 290 mW (on 1 cm² collector pad), and Tj ≤ 150 °C. Its pulsed hFE range (250–600) enables stable current amplification across temperature extremes (−65 °C to +150 °C).
Key electrical behaviors include VCE(sat) ≤ 700 mV at IC = 500 mA / IB = 50 mA, VBE ≈ 1.2 V under same conditions, and fT = 100 MHz at VCE = 5 V, IC = 10 mA - confirming suitability for medium-speed digital switching and analog signal buffering.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage before breakdown; defines rail compatibility up to 42 V DC systems. |
| IC | 500 mA continuous - Supports load switching up to 0.5 A without forced cooling on standard FR4 PCB. |
| hFE | 250–600 at VCE = 1 V, IC = 100 mA - Ensures predictable base drive requirements for stable biasing in amplifier stages. |
| VCE(sat) | ≤ 700 mV at IC = 500 mA, IB = 50 mA - Minimizes conduction loss and self-heating during saturated switching. |
| Rth(j-a) | 431 K/W (1 cm² collector pad) - Enables thermal design margin of ~125 °C rise at full power on optimized layout. |
| fT | 100 MHz - Supports clean square-wave switching up to ~10 MHz with minimal rise/fall time degradation. |
Pinout & Package
SOT323 (SC-70) plastic surface-mounted package with 3 leads; footprint dimensions per Fig. 17: 2.65 mm × 2.35 mm body, 0.65 mm lead pitch, 0.55 mm solder pad width (3×), and 1.325 mm pad length.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Current-controlled input node; requires 1.2–2.0 mA typical drive for 100 mA collector output in linear mode. |
| 2 | Emitter (E) | Reference terminal for bias network; connects directly to ground or emitter resistor in common-emitter configuration. |
| 3 | Collector (C) | High-current output node; thermally coupled to PCB copper area to sustain 290 mW dissipation at ambient ≤ 75 °C. |
Key Features
| Feature | Design Value |
|---|---|
| Three hFE variants | BC817-40W offers 250–600 gain spread - simplifies production binning and eliminates manual gain matching in volume designs. |
| Low VCE(sat) | ≤ 700 mV at full rated current - reduces power loss by >30% vs. legacy BC817-16W in high-duty-cycle switching. |
| Thermal robustness | Rth(j-a) = 431 K/W with 1 cm² copper - allows operation at 125 °C ambient when mounted per Fig. 17 footprint. |
| Small-footprint SOT323 | 2.65 mm × 2.35 mm outline - saves >40% board area vs. SOT23 while maintaining reflow compatibility with standard pick-and-place. |
Applications
| LED Driver Circuit | Microcontroller GPIO Expander |
|---|---|
|
Use Scenario: Driving 20 mA indicator LEDs from 3.3 V MCU outputs with current limiting via base resistor. IC Role / Device Role / Timing Role: NPN switch operating in saturation region; turns LED on/off within <100 ns. Use Value: VCE(sat) ≤ 700 mV ensures >3.0 V forward drop across LED at full brightness, eliminating need for level-shifting. |
Use Scenario: Amplifying weak sensor signals (e.g., thermistor divider) into 0–3.3 V range for ADC input. IC Role / Device Role / Timing Role: Common-emitter amplifier with fixed bias; provides 20–40 dB voltage gain at DC–10 kHz. Use Value: hFE ≥ 250 guarantees stable gain across −40 °C to +85 °C, reducing calibration drift in portable instruments. |
| Power Supply Enable Switch | Relay Coil Driver |
|
Use Scenario: Enabling/disabling 5 V LDO output using 1.8 V logic signal in battery-powered IoT node. IC Role / Device Role / Timing Role: Low-side enable switch; handles 300 mA inrush current during LDO startup. Use Value: ICM = 1 A peak rating absorbs transient surges without latch-up, improving system reliability. |
Use Scenario: Driving 12 V, 400 Ω relay coil (30 mA) from microcontroller with flyback diode protection. IC Role / Device Role / Timing Role: Saturated switch controlling coil energization/de-energization. Use Value: 45 V VCEO safely clamps flyback spikes up to 40 V, eliminating need for external TVS in compact designs. |
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 | SOT23 package (larger footprint, higher Rth(j-a) = 625 K/W); identical electrical specs. | Less suitable for ultra-dense layouts; requires larger PCB area and heatsinking for same power handling. | Select when existing SOT23 land pattern is fixed and thermal margin >100 K/W is acceptable. |
| MMBT3904LT1G | hFE = 100–300 (lower gain spread); VCEO = 40 V; same SOT23 package. | Lower gain necessitates higher base drive current; 40 V rating limits use in 36 V industrial rails. | Choose only if cost sensitivity outweighs gain stability and 45 V headroom requirements. |
Compared with BC817-40W/ZLF, BC817-40 trades miniaturization for easier hand-soldering and lower assembly cost, while MMBT3904LT1G sacrifices gain consistency and voltage margin to meet legacy footprint constraints - making BC817-40W/ZLF optimal for new designs prioritizing density, thermal performance, and predictable biasing.
Availability
BC817-40W/ZLF is available at Aetrix Electronics and suitable for LED driver circuits, microcontroller GPIO expansion, power supply enable switches, and relay coil drivers requiring stable component supply across automotive-grade-adjacent industrial and consumer programs.
Supply support for BC817-40W/ZLF 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 and standard logic solutions.
The BC817W series targets cost-sensitive, space-constrained applications in consumer electronics and industrial control, delivering consistent gain grading and thermal performance in ultra-small packages.
FAQ
What is the maximum allowable junction temperature for BC817-40W/ZLF?
The absolute maximum junction temperature is 150 °C, as specified in Table 6 of the Nexperia datasheet Rev. 8. Operation above this threshold causes irreversible degradation of hFE and increased leakage. Derating begins at 25 °C ambient, with total power dissipation dropping linearly to zero at 150 °C junction temperature.
Does BC817-40W/ZLF support automotive applications?
No - the BC817W series is explicitly non-automotive qualified per Section 14 of the datasheet. It lacks AEC-Q101 stress testing and automotive-grade process controls. For automotive use, Nexperia recommends the BC817-Q series, which undergoes full qualification including temperature cycling, humidity testing, and HTOL.
How does the SOT323 package affect thermal performance compared to SOT23?
The SOT323 package reduces thermal resistance from junction to ambient to 431 K/W (with 1 cm² collector pad) versus 625 K/W for SOT23 under identical mounting conditions. This 31% improvement allows 290 mW continuous dissipation at 75 °C ambient, whereas SOT23 versions require derating beyond 50 °C ambient for the same power level.
What is the meaning of the 'ZLF' suffix in BC817-40W/ZLF?
The '/ZLF' suffix denotes Nexperia's lead-free, halogen-free, and RoHS-compliant packaging - specifically, matte tin (Sn) termination on copper leadframe with no brominated flame retardants in the molding compound. It meets JEDEC J-STD-020D moisture sensitivity level 1 (MSL-1) and supports standard Pb-free reflow profiles.
BC817-40W/ZLF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- SC-70, SOT-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Transistor Type:
- -
- Current - Collector (Ic) (Max):
- -
- Voltage - Collector Emitter Breakdown (Max):
- -
- Vce Saturation (Max) @ Ib, Ic:
- -
- Current - Collector Cutoff (Max):
- -
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- -
- Power - Max:
- -
- Frequency - Transition:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-323
BC817-40W/ZLF FAQ
1.How can I place an order for BC817-40W/ZLF through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817-40W/ZLF 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 BC817-40W/ZLF reliable?
The price and inventory of BC817-40W/ZLF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817-40W/ZLF is usually 5 days.
3.What payment methods are accepted for BC817-40W/ZLF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817-40W/ZLF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817-40W/ZLF?
BC817-40W/ZLF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817-40W/ZLF 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 BC817-40W/ZLF?
For technical support, including BC817-40W/ZLF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817-40W/ZLF requirements.
6.How does Aetrix verify that BC817-40W/ZLF is sourced from the original manufacturer or authorized distributors?
All BC817-40W/ZLF 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 BC817-40W/ZLF meets industry standards.
7.What is the process for return or replacement of BC817-40W/ZLF?
All BC817-40W/ZLF units undergo pre-shipment inspection (PSI). If there is an issue with BC817-40W/ZLF, 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 BC817-40W/ZLF part is unused and in its original packaging.
Return procedure for BC817-40W/ZLF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC817-40W/ZLF Tags
-
MMBT3906LT1G
onsemi
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MMBT3904-7-F
Diodes Incorporated
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MMBT3904LT1G
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MMBT3906-7-F
Diodes Incorporated
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MMBT3904-TP
Micro Commercial Co
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MMBT2222A-7-F
Diodes Incorporated
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BC846BLT1G
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BC847B,215
Nexperia USA Inc.
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SMMBT3904LT1G
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MMBT2222A-TP
Micro Commercial Co
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