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Nexperia USA Inc. BC817-40W,135
- Part No.:
- BC817-40W,135
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- SC-70, SOT-323
- Datasheet:
-
BC817-40W,135.pdf
- Description:
- TRANS NPN 45V 0.5A SOT-323
- Quantity:
- Payment:
- Shipping:
Inventory:191,069
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Product details
Overview
BC817-40W,135 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 stable DC gain across temperature and supports peak collector current up to 1 A for short pulses in consumer power management and signal conditioning circuits.
For engineers reviewing the BC817-40W,135 datasheet, BC817-40W,135 pinout, BC817-40W,135 application, or BC817-40W,135 equivalent, this page provides verified pin configuration, thermal derating curves, saturation voltage behavior under IC/IB = 10, junction-to-ambient thermal resistance (431 K/W on 1 cm² collector pad), and direct alternatives with documented hFE and VCE(sat) trade-offs.
Technical Context
This NPN bipolar junction transistor operates in active, saturation, and cutoff regions with defined absolute maximum ratings: VCEO = 45 V, IC = 500 mA continuous, and Ptot = 290 mW on FR4 PCB with 1 cm² collector pad. Its pulsed operation supports tp ≤ 300 μs at δ ≤ 0.02, enabling reliable use in PWM-driven LED drivers and logic-level interface stages.
The device exhibits VBE(sat) ≤ 1.2 V and VCE(sat) ≤ 700 mV at IC = 500 mA / IB = 50 mA, with fT = 100 MHz at VCE = 5 V, IC = 10 mA, confirming suitability for audio preamplifier gain stages and low-frequency switching above 10 kHz.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage before breakdown in open-base configuration; defines rail compatibility in 3.3 V/5 V/12 V logic interfaces. |
| IC | 500 mA - Continuous DC collector current rating; sets upper limit for load switching in relay drivers and sensor biasing networks. |
| hFE | 250–600 - DC current gain range at VCE = 1 V, IC = 100 mA; enables predictable base drive sizing for stable amplifier biasing. |
| VCE(sat) | ≤ 700 mV - Collector-emitter saturation voltage at IC = 500 mA / IB = 50 mA; minimizes conduction loss in high-duty-cycle switch applications. |
| fT | 100 MHz - Transition frequency at VCE = 5 V, IC = 10 mA; supports small-signal amplification up to mid-audio frequencies. |
| Rth(j-a) | 431 K/W - Junction-to-ambient thermal resistance on FR4 with 1 cm² collector pad; determines required PCB copper area for thermal compliance at full IC. |
Pinout & Package
SOT323 (SC-70) plastic surface-mounted package with 3 leads, 1.35 mm × 1.15 mm footprint, 0.65 mm lead pitch, and 0.25 mm max A1 height - optimized for high-density PCB layouts and reflow soldering per IPC-7095.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Control terminal accepting current-limited input to modulate collector current; requires series resistor to limit IB per hFE target. |
| 2 | Emitter (E) | Reference node tied to ground or common return path; establishes current reference for VBE-driven operation. |
| 3 | Collector (C) | Output terminal sourcing current to load; connected to higher-potential rail in low-side switch configurations. |
Key Features
| Feature | Design Value |
|---|---|
| Three hFE selections | BC817-40W offers 250–600 gain range - enables precise base drive optimization without external feedback components in fixed-gain amplifiers. |
| Low VCE(sat) | ≤ 700 mV at IC = 500 mA - reduces power dissipation by >30% vs. standard 1 V saturation devices, critical for thermally constrained IoT nodes. |
| High fT | 100 MHz - supports bandwidth-critical functions like tone generation and analog front-end buffering without gain roll-off. |
| Thermal robustness | 150 °C max junction temperature with 431 K/W Rth(j-a) on enhanced pad - allows sustained operation in sealed enclosures up to 85 °C ambient. |
Applications
| LED Driver Circuit | Microcontroller GPIO Interface |
|---|---|
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: Low-side NPN switch controlling LED anode-to-rail current path; operates in saturation with <1 µs turn-on delay. Use Value: VCE(sat) ≤ 700 mV ensures >95% LED forward voltage utilization and eliminates need for heat sinking at 20 mA. |
Use Scenario: Level-shifting 3.3 V logic signals to control 5 V or 12 V peripheral enable lines. IC Role / Device Role / Timing Role: Digital translator providing galvanic isolation between voltage domains; biased into hard saturation for clean logic transitions. Use Value: hFE ≥ 250 guarantees full saturation with ≤ 100 µA base drive, reducing GPIO loading below MCU leakage thresholds. |
| Audio Pre-amplifier Stage | Relay Coil Driver |
Use Scenario: Single-transistor common-emitter amplifier boosting microphone output to line-level signals in portable audio recorders. IC Role / Device Role / Timing Role: Linear-mode amplifier with emitter degeneration resistor; operates in active region with VCE ≈ 2.5 V for 3.3 V supply. Use Value: fT = 100 MHz ensures flat gain response up to 20 kHz, while hFE consistency minimizes distortion across production batches. |
Use Scenario: Switching 12 V, 400 mA relay coils in industrial control panels using microcontroller outputs. IC Role / Device Role / Timing Role: High-current saturated switch absorbing coil flyback energy via external diode; handles ICM = 1 A pulses during turn-off. Use Value: 500 mA continuous rating and 1 A pulse capability prevent thermal runaway during repeated actuation cycles at 1 Hz. |
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 |
|---|---|---|---|
| BC847BW,115 | Lower VCEO = 45 V (same), but hFE = 200–450 and VCE(sat) = 600 mV at same conditions. | Suitable for lower-gain, lower-loss switching where tighter hFE tolerance is acceptable. | Select when prioritizing marginally lower saturation loss over wide gain spread. |
| MMBT3904LT1G | Same VCEO = 40 V, hFE = 100–300, VCE(sat) = 300 mV at IC = 10 mA but degrades to 950 mV at 500 mA. | Better for low-current (<50 mA) digital switching; less suitable for 500 mA loads due to higher VCE(sat) at full rating. | Choose only for sub-100 mA applications where ultra-low VCE(sat) at light load matters more than full-rated performance. |
Compared with BC817-40W,135, BC847BW,115 trades wider hFE range for slightly lower VCE(sat), while MMBT3904LT1G offers superior low-current efficiency but fails to maintain low saturation voltage at 500 mA - making BC817-40W,135 the optimal choice for high-current, gain-stable switching in space-constrained designs.
Availability
BC817-40W,135 is available at Aetrix Electronics and suitable for LED driver circuits, microcontroller GPIO interfacing, audio pre-amplifier stages, and relay coil driving requiring stable component supply across automotive infotainment, industrial HMI, and consumer electronics production.
Supply support for BC817-40W,135 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 industrial-grade components.
The BC817W series targets cost-sensitive, space-constrained applications demanding consistent DC gain, low saturation voltage, and robust thermal performance in SOT323 packaging - designed specifically for consumer, computing, and industrial signal conditioning and power switching.
FAQ
What is the maximum allowable junction temperature for BC817-40W,135?
The absolute maximum junction temperature is 150 °C, validated per IEC 60134 limiting values. Operation above this threshold risks permanent parametric shift or bond-wire failure. Derating begins at Tamb = 25 °C, with total power dissipation dropping linearly to zero at 150 °C ambient when mounted on FR4 with 1 cm² collector pad.
Does BC817-40W,135 support automotive applications?
No - BC817-40W,135 is explicitly non-automotive qualified per Nexperia's revision history (v.8, July 2022). It lacks AEC-Q101 qualification, automotive-grade screening, and extended temperature validation. For automotive use, Nexperia recommends BC817-40Q variants with full AEC-Q101 compliance and -40 °C to +150 °C operation.
How does the hFE of BC817-40W,135 vary with temperature?
hFE increases with junction temperature: typical gain rises ~0.5%/°C from 25 °C to 125 °C, peaking near 150 °C. Figure 12 shows hFE = 600 at IC = 100 mA, VCE = 1 V, and Tamb = 150 °C - critical for thermal stability analysis in enclosed power supplies.
Can BC817-40W,135 replace BC817-25W in existing designs?
Yes - BC817-40W,135 is a direct upgrade with identical pinout, package, and voltage/current ratings, but offers higher minimum hFE (250 vs. 160). This improves base drive margin and reduces sensitivity to resistor tolerance in amplifier bias networks without requiring layout changes.
BC817-40W,135 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- 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:
- 250 @ 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
BC817-40W,135 FAQ
1.How can I place an order for BC817-40W,135 through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817-40W,135 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,135 reliable?
The price and inventory of BC817-40W,135 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,135 is usually 5 days.
3.What payment methods are accepted for BC817-40W,135?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817-40W,135 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817-40W,135?
BC817-40W,135 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817-40W,135 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,135?
For technical support, including BC817-40W,135 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817-40W,135 requirements.
6.How does Aetrix verify that BC817-40W,135 is sourced from the original manufacturer or authorized distributors?
All BC817-40W,135 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,135 meets industry standards.
7.What is the process for return or replacement of BC817-40W,135?
All BC817-40W,135 units undergo pre-shipment inspection (PSI). If there is an issue with BC817-40W,135, 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,135 part is unused and in its original packaging.
Return procedure for BC817-40W,135:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC817-40W,135 Tags
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MMBT3906LT1G
onsemi
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MMBT3904-7-F
Diodes Incorporated
-
MMBT3904LT1G
onsemi
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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
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MMBT2222ALT1G
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