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Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

Nexperia USA Inc. BC817-40/SNVL

Name: BC817-40/SNVL
Brand: Nexperia USA Inc.
SKU: BC817-40/SNVL
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BC817-40/SNVL

Manufacturer:: Nexperia USA Inc.

Category:: Single Bipolar Transistors

Package:: TO-236-3, SC-59, SOT-23-3

Datasheet:: BC817-40/SNVL.pdf

Description:: TRANS NPN 45V 0.5A TO-236AB

Quantity:: RFQ Add To RFQ list

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Inventory:9,900

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Product details

Overview

BC817-40/SNVL from Nexperia is a 45 V, 500 mA NPN general-purpose transistor in SOT23 (TO-236AB) surface-mount package, optimized for switching and linear amplification with h_FE = 250–600 at V_CE = 1 V, I_C = 100 mA, used in power supply control circuits, signal buffering, and discrete logic interface stages.

For engineers reviewing the BC817-40/SNVL datasheet, BC817-40/SNVL pinout, BC817-40/SNVL application, or BC817-40/SNVL equivalent, key selection criteria include DC current gain range, V_CEO rating, thermal resistance on FR4 PCB, saturation voltage under 500 mA load, and SOT23 footprint compatibility with automated assembly.

Technical Context

This NPN bipolar junction transistor operates in active, saturation, and cutoff regions with defined absolute maximum ratings: V_CEO = 45 V, I_C = 500 mA continuous, and P_tot = 345 mW on 1 cm² collector pad. Its pulsed operation supports I_CM = 1 A (t_p ≤ 1 ms), enabling short-duration overload handling in relay drivers and motor commutation circuits.

The device exhibits V_CE(sat) ≤ 700 mV at I_C = 500 mA and I_B = 50 mA, and V_BE ≈ 1.2 V under same conditions, ensuring predictable base drive requirements. Thermal resistance R_th(j-a) is 362 K/W when mounted on FR4 with extended collector pad, critical for thermal design in compact power management modules.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	45 V - Maximum safe collector-emitter voltage before breakdown; defines upper rail limit in low-voltage switching applications.
I_C	500 mA - Continuous collector current rating; sets maximum steady-state load capability in driver stages.
h_FE	250–600 - DC current gain at V_CE = 1 V, I_C = 100 mA; determines required base drive current for target collector load.
V_CE(sat)	≤ 700 mV - Collector-emitter saturation voltage at I_C = 500 mA, I_B = 50 mA; directly impacts conduction loss and heat generation.
R_th(j-a)	362 K/W - Junction-to-ambient thermal resistance with 1 cm² collector pad; enables thermal budget calculation for ambient temperatures up to 125 °C.
f_T	100 MHz - Transition frequency at V_CE = 5 V, I_C = 10 mA; indicates usable bandwidth for small-signal amplification up to ~10 MHz.

Pinout & Package

SOT23 (TO-236AB) plastic surface-mounted package with 3 leads; 1.9 mm × 1.1 mm body, 0.45 mm nominal thickness, standard reflow-compatible footprint per Figure 17.

Pin/Terminal	Circuit Role	Design Meaning
1	Base (B)	Current-controlled input node; requires ≥12 mA base drive for full 500 mA saturation under typical conditions.
2	Emitter (E)	Reference terminal for biasing; connected to ground or low-side return path in common-emitter configurations.
3	Collector (C)	High-current output node; thermally coupled to PCB copper for heat dissipation; must be routed with adequate trace width.

Key Features

Feature	Design Value
Three h_FE grades	BC817-40 provides 250–600 gain range-enables precise base resistor selection for consistent switching thresholds across production batches.
Low V_CE(sat)	≤700 mV at 500 mA ensures <125 mW conduction loss, reducing thermal stress in space-constrained 5 V/3.3 V logic-level driver designs.
SOT23 footprint	Standardized 3-pin SMT outline allows drop-in replacement in existing layouts and compatibility with high-speed pick-and-place equipment.
FR4 thermal performance	362 K/W R_th(j-a) with 1 cm² collector pad supports reliable operation up to 125 °C ambient without heatsinking.

Applications

Power Supply Enable Switch

Microcontroller GPIO Buffer

Use Scenario: Enabling/disabling 12 V auxiliary rails in embedded power sequencers using 3.3 V MCU outputs.

IC Role / Device Role / Timing Role: NPN switch controlling PMOS gate pull-down or NMOS source enable path.

Use Value: V_CEO = 45 V safely accommodates 12 V rail transients; h_FE ≥250 ensures full saturation with ≤20 µA MCU drive current.

Use Scenario: Driving LED indicators or optocoupler inputs from low-current microcontroller pins.

IC Role / Device Role / Timing Role: Current amplifier converting 4 mA GPIO output into 20–50 mA load current.

Use Value: V_CE(sat) ≤700 mV minimizes voltage drop across series resistor, preserving LED forward voltage margin.

Relay Coil Driver

Discrete Logic Level Shifter

Use Scenario: Controlling 5 V/12 V electromagnetic relays in industrial I/O modules.

IC Role / Device Role / Timing Role: Low-side switch sinking relay coil current during activation.

Use Value: I_CM = 1 A handles relay inrush current spikes; built-in flyback diode not required due to robust V_CEO margin.

Use Scenario: Translating 1.8 V logic signals to 5 V domains in mixed-voltage sensor interfaces.

IC Role / Device Role / Timing Role: Common-emitter inverter with fixed gain and defined threshold via base bias network.

Use Value: Predictable h_FE range enables stable switching point design; f_T = 100 MHz supports >1 MHz signal edges.

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
BC847C/SNVL	Lower V_CEO = 45 V (same), but h_FE = 420–800 at I_C = 2 mA; higher gain at low current, lower max I_C = 100 mA.	Not suitable for 500 mA loads; better for signal amplification than power switching.	Select BC847C only when gain stability at µA–mA bias levels is prioritized over current capacity.
MMBT3904LT1G	V_CEO = 40 V, I_C = 200 mA, h_FE = 100–300 at I_C = 10 mA; smaller gain spread but lower voltage and current ratings.	Limited to sub-200 mA loads and ≤40 V systems; less margin for transient overvoltage.	Choose MMBT3904LT1G only for cost-sensitive, low-power signal routing where 45 V/500 mA capability is unnecessary.

Compared with BC817-40/SNVL, BC847C offers higher gain at low currents but cannot sustain 500 mA, while MMBT3904LT1G trades voltage/current headroom for broader availability and lower unit cost in non-demanding signal paths.

Availability

BC817-40/SNVL is available at Aetrix Electronics and suitable for power supply enable switches, microcontroller GPIO buffers, and relay coil drivers requiring stable component supply, consistent h_FE grading, and SOT23 assembly compatibility.

Supply support for BC817-40/SNVL 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 for automotive, industrial, and consumer markets.

The BC817 series targets cost-effective, robust discrete solutions for general-purpose switching and amplification in space-constrained, thermally demanding applications.

FAQ

What is the maximum continuous collector current for BC817-40/SNVL?

The maximum continuous collector current is 500 mA at T_amb ≤ 25 °C with proper PCB thermal management. Derating applies above 25 °C ambient; at 125 °C, usable I_C drops to approximately 250 mA based on the 362 K/W thermal resistance and 150 °C max junction temperature.

Does BC817-40/SNVL require a base resistor in switching applications?

Yes - a base resistor is mandatory to limit I_B and ensure predictable saturation. For 500 mA collector current with h_FE ≥250, minimum I_B = 2 mA is required; typical design uses 4.7 kΩ from 3.3 V or 10 kΩ from 5 V to provide 0.7–0.5 mA margin.

Can BC817-40/SNVL replace BC817-25 in an existing design?

Yes, with verification of gain-dependent timing margins. BC817-40 has higher minimum h_FE (250 vs. 160), resulting in lower required base drive and faster turn-on in saturated switching. However, V_CE(sat) and thermal characteristics remain identical, so layout and thermal design need no changes.

Is BC817-40/SNVL qualified for automotive applications?

No - this variant is non-automotive qualified per Nexperia's revision history (v.8, July 2022). Automotive-grade equivalents such as BC817-40-Q include additional AEC-Q101 testing, extended temperature validation, and PPAP documentation; use only certified -Q parts in safety-critical vehicle systems.

BC817-40/SNVL 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:: 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:: 250 mW

Frequency - Transition:: 100MHz

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: TO-236AB

BC817-40/SNVL FAQ

1.How can I place an order for BC817-40/SNVL through Aetrix?

Please submit a Request for Quotation (RFQ) for BC817-40/SNVL 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 BC817-40/SNVL reliable?

The price and inventory of BC817-40/SNVL are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817-40/SNVL is usually 5 days.

3.What payment methods are accepted for BC817-40/SNVL?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817-40/SNVL transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC817-40/SNVL?

BC817-40/SNVL orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC817-40/SNVL 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 BC817-40/SNVL?

For technical support, including BC817-40/SNVL datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817-40/SNVL requirements.

6.How does Aetrix verify that BC817-40/SNVL is sourced from the original manufacturer or authorized distributors?

All BC817-40/SNVL 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 BC817-40/SNVL meets industry standards.

7.What is the process for return or replacement of BC817-40/SNVL?

All BC817-40/SNVL units undergo pre-shipment inspection (PSI). If there is an issue with BC817-40/SNVL, 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 BC817-40/SNVL part is unused and in its original packaging.

Return procedure for BC817-40/SNVL:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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