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Nexperia USA Inc. BC817-40W/MIX
- Part No.:
- BC817-40W/MIX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- SC-70, SOT-323
- Datasheet:
-
BC817-40W/MIX.pdf
- Description:
- TRANS NPN 45V 0.5A SOT-323
- Quantity:
- Payment:
- Shipping:
Inventory:9,938
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Product details
Overview
BC817-40W 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 in space-constrained PCBs. It delivers DC current gain (hFE) of 250–600 at VCE = 1 V and IC = 100 mA, supports 1 A peak collector current, and features 700 mV VCE(sat) at IC = 500 mA / IB = 50 mA - enabling efficient low-voltage logic-level drive in portable power management circuits.
For engineers reviewing the BC817-40W datasheet, BC817-40W pinout, BC817-40W application, or BC817-40W equivalent, key selection criteria include its guaranteed hFE range, thermal resistance (Rth(j-a) = 431 K/W on 1 cm² collector pad), SOT323 footprint compatibility, and non-automotive qualification status per Rev. 8 (2022).
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 continuous, and Tj ≤ 150 °C. Its pulsed operation supports ICM = 1 A (tp ≤ 1 ms), and base-emitter breakdown voltage is rated at 5 V.
The device exhibits fT = 100 MHz at VCE = 5 V, IC = 10 mA, confirming suitability for medium-frequency signal amplification. Collector capacitance Cc is 3 pF at VCB = 10 V, supporting stable high-speed switching with minimal Miller effect in low-noise amplifier stages.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage before avalanche breakdown under open-base conditions. |
| IC | 500 mA - Continuous DC collector current rating defining steady-state power handling capability. |
| hFE | 250–600 - Guaranteed DC current gain range at VCE = 1 V, IC = 100 mA, enabling predictable base drive sizing. |
| VCE(sat) | 700 mV - Collector-emitter saturation voltage at IC = 500 mA / IB = 50 mA, directly determining conduction loss in switch applications. |
| Rth(j-a) | 431 K/W - Thermal resistance from junction to ambient when mounted on FR4 PCB with 1 cm² collector copper pad, critical for thermal design margin. |
| fT | 100 MHz - Transition frequency indicating usable bandwidth for small-signal amplification up to mid-VHF range. |
| Cc | 3 pF - Collector capacitance at VCB = 10 V, limiting high-frequency gain roll-off and affecting switching speed. |
Pinout & Package
SOT323 (SC-70) plastic surface-mounted package: 3-terminal, ultra-small outline (2.2 mm × 1.35 mm × 0.95 mm), optimized for high-density PCB layouts and reflow soldering.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Control terminal; requires ~1.2 V forward bias and precise current limiting (e.g., 50 mA for 500 mA IC) to achieve saturation. |
| 2 | Emitter (E) | Current return path; internally connected to substrate; must be tied to lowest potential in common-emitter configuration. |
| 3 | Collector (C) | High-current output terminal; thermally coupled to largest copper area on PCB to manage 290 mW Ptot dissipation. |
Key Features
| Feature | Design Value |
|---|---|
| Three hFE variants | BC817-40W offers 250–600 hFE, enabling precise gain matching across production batches without external feedback compensation. |
| Low VCE(sat) | 700 mV max ensures <1.25 mW conduction loss at 500 mA, reducing heat generation in battery-powered load switches. |
| SOT323 footprint | Standardized SC-70 land pattern (2.65 mm × 2.35 mm solder mask opening) enables drop-in replacement and automated assembly compatibility. |
| 150 °C junction rating | Allows operation in industrial environments up to +85 °C ambient with adequate copper thermal relief, verified per IEC 60134 limiting values. |
Applications
| LED Driver Circuit | Microcontroller GPIO Expander |
|---|---|
|
Use Scenario: Driving 20 mA white LEDs from 3.3 V MCU outputs in handheld medical devices. IC Role / Device Role / Timing Role: NPN switch controlling LED anode current; base driven directly by MCU GPIO with series resistor. Use Value: 700 mV VCE(sat) preserves >3.0 V across LED for consistent brightness; 250–600 hFE ensures reliable turn-on with 5–10 µA base leakage margin. |
Use Scenario: Level-shifting and current boosting for 5 V peripheral interfaces controlled by 3.3 V microcontrollers. IC Role / Device Role / Timing Role: Single-transistor level translator enabling bidirectional signal conditioning between mixed-voltage domains. Use Value: 45 V VCEO provides headroom against ESD transients; 100 MHz fT supports clean 1–5 MHz digital signal edges without overshoot. |
| DC Motor Control Stage | Audio Pre-amplifier Input Stage |
|
Use Scenario: Low-side switching of 12 V, 300 mA brushed DC motors in robotics actuators. IC Role / Device Role / Timing Role: Power switch in common-emitter configuration; base driven by PWM controller via current-limiting resistor. Use Value: 500 mA IC rating matches motor stall current; 1 A ICM handles startup surges; 431 K/W Rth(j-a) prevents thermal shutdown during 100 ms pulses. |
Use Scenario: First-stage gain block in portable audio recorder front-end, amplifying electret microphone signals. IC Role / Device Role / Timing Role: Common-emitter amplifier with emitter degeneration resistor for linearity and bias stability. Use Value: 100 MHz fT and 3 pF Cc support flat 20 Hz–20 kHz response; 250–600 hFE allows fixed-bias design with ±10% gain tolerance. |
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 | Lower VCEO (45 V same), but hFE = 200–450 and higher VBE (~1.3 V); identical SOT323 package. | Less suitable for high-gain analog stages requiring >500 hFE; better for digital switching where tighter hFE tolerance matters. | Select BC847BW only if lower base current demand is prioritized over gain headroom and thermal margin. |
| MMBT3904LT1G | Same VCEO/IC, but hFE = 100–300 and Rth(j-a) = 625 K/W (standard footprint); SOT23 package. | Requires larger PCB area and delivers lower gain; less thermally robust at full IC due to higher thermal resistance. | Choose MMBT3904LT1G only when legacy SOT23 footprint compatibility is mandatory and gain >250 is not required. |
Compared with BC817-40W, BC847BW trades gain breadth for tighter hFE distribution, while MMBT3904LT1G sacrifices thermal performance and gain for SOT23 mechanical compatibility - making BC817-40W optimal for new designs demanding high gain, low saturation loss, and compact thermal management.
Availability
BC817-40W is available at Aetrix Electronics and suitable for LED driver circuits, microcontroller GPIO expansion, and DC motor control stages requiring stable component supply, consistent hFE binning, and SOT323 footprint reliability.
Supply support for BC817-40W 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, industrial, and mobile applications.
The BC817W series targets cost-sensitive, space-constrained consumer and industrial electronics requiring robust general-purpose NPN transistors with guaranteed gain bins and standardized SMD packaging.
FAQ
Is BC817-40W qualified for automotive applications?
No. Per Nexperia Rev. 8 (2022) datasheet, BC817-40W is explicitly designated as non-automotive qualified. It lacks AEC-Q101 stress testing and automotive-grade process controls. For automotive use, select the -Q qualified variant (e.g., BC817-40W-Q) or consult Nexperia's official automotive portfolio.
What is the maximum allowable base current for continuous operation?
The absolute maximum peak base current is 200 mA (single pulse, tp ≤ 1 ms), but continuous operation must limit IB to ensure junction temperature stays ≤150 °C. At IC = 500 mA and hFE = 250, nominal IB = 2 mA; derating per Rth(j-a) and ambient temperature is required above 25 °C.
Can BC817-40W replace BC817-25W in existing designs?
Yes, with functional improvement: BC817-40W has higher minimum hFE (250 vs. 160) and identical VCEO, IC, and package. No layout or bias changes are needed, and it enhances gain margin in amplification or reduces base drive requirements in switching applications.
What is the recommended PCB layout for thermal performance?
For optimal thermal performance, use a 1 cm² copper pad connected to the collector (Pin 3) on the top layer, with ≥4 thermal vias to inner/ground planes. The datasheet specifies Rth(j-a) = 431 K/W only under this condition; standard footprint mounting yields 625 K/W, reducing safe continuous IC by ~30%.
BC817-40W/MIX 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:
- 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/MIX FAQ
1.How can I place an order for BC817-40W/MIX through Aetrix?
Please submit a Request for Quotation (RFQ) for BC817-40W/MIX 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/MIX reliable?
The price and inventory of BC817-40W/MIX 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/MIX is usually 5 days.
3.What payment methods are accepted for BC817-40W/MIX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817-40W/MIX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC817-40W/MIX?
BC817-40W/MIX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC817-40W/MIX 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/MIX?
For technical support, including BC817-40W/MIX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817-40W/MIX requirements.
6.How does Aetrix verify that BC817-40W/MIX is sourced from the original manufacturer or authorized distributors?
All BC817-40W/MIX 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/MIX meets industry standards.
7.What is the process for return or replacement of BC817-40W/MIX?
All BC817-40W/MIX units undergo pre-shipment inspection (PSI). If there is an issue with BC817-40W/MIX, 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/MIX part is unused and in its original packaging.
Return procedure for BC817-40W/MIX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC817-40W/MIX Tags
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Diodes Incorporated
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MMBT3904-TP
Micro Commercial Co
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MMBT2222A-7-F
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BC847B,215
Nexperia USA Inc.
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MMBT2222A-TP
Micro Commercial Co
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