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

Nexperia USA Inc. BC817-25,235

Name: BC817-25,235
Brand: Nexperia USA Inc.
SKU: BC817-25,235
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BC817-25,235

Manufacturer:: Nexperia USA Inc.

Category:: Single Bipolar Transistors

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

Datasheet:: BC817-25,235.pdf

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

Quantity:: RFQ Add To RFQ list

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Product details

Overview

BC817-25,235 from Nexperia is an NPN general-purpose bipolar junction transistor in SOT23 (TO-236AB) package, rated for 45 V V_CEO, 500 mA continuous collector current, and DC current gain (h_FE) of 160–400 at V_CE = 1 V and I_C = 100 mA. It serves as a low-voltage switching or linear amplification element in discrete logic interfaces, LED drivers, and power management stages.

For engineers reviewing the BC817-25,235 datasheet, BC817-25,235 pinout, BC817-25,235 application, or BC817-25,235 equivalent, key selection criteria include verified h_FE binning (160–400), SOT23 thermal derating behavior, V_CE(sat) ≤ 700 mV at I_C = 500 mA / I_B = 50 mA, and compatibility with standard FR4 PCB layouts using tin-plated copper.

Technical Context

The BC817-25,235 operates as a silicon-based NPN BJT with base-controlled current amplification. Its h_FE binning (160–400) ensures predictable gain in bias-stable amplifier designs and reliable saturation in digital switching applications where I_C/I_B = 10 is used.

It features absolute maximum ratings including 45 V V_CEO, 500 mA I_C, and 150 °C T_j, with thermal resistance R_th(j-a) of 500 K/W on standard FR4 and 362 K/W with enhanced 1 cm² collector pad - directly impacting power handling in compact PCB layouts.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	45 V - Maximum safe collector-emitter voltage before breakdown; defines upper rail limit in 24 V or 36 V switching circuits.
I_C	500 mA - Continuous DC collector current rating; supports load switching up to ~200 mW dissipation at room temperature.
h_FE	160–400 - Confirmed DC current gain range at V_CE = 1 V, I_C = 100 mA; enables precise base resistor calculation for saturated switch operation.
V_CE(sat)	≤ 700 mV - Measured at I_C = 500 mA, I_B = 50 mA; ensures low conduction loss and minimal self-heating in high-duty-cycle switches.
f_T	100 MHz - Transition frequency at V_CE = 5 V, I_C = 10 mA; supports small-signal amplification up to low-VHF band, not RF power stages.
R_th(j-a)	500 K/W - Junction-to-ambient thermal resistance on standard FR4; requires layout-aware heatsinking for >150 mW sustained power.

Pinout & Package

SOT23 (TO-236AB) plastic surface-mounted package with 3 leads; 1.3 mm × 2.9 mm footprint, 1.1 mm height, and standard reflow-compatible solder pads per Figure 17.

Pin/Terminal	Circuit Role	Design Meaning
1	Base (B)	Current-controlled input node; requires series resistor to limit I_B and ensure saturation at target I_C.
2	Emitter (E)	Reference terminal for bias network; connected to ground or low-side return path in common-emitter configurations.
3	Collector (C)	High-current output node; routed to load or pull-up; thermally coupled to PCB copper for power dissipation.

Key Features

Feature	Design Value
Three h_FE bins	BC817-25 provides 160–400 h_FE, enabling consistent gain matching across production batches without manual sorting.
Low V_CE(sat)	≤ 700 mV at full 500 mA load ensures <100 mW conduction loss, reducing thermal stress in space-constrained designs.
SOT23 thermal performance	362 K/W R_th(j-a) with 1 cm² collector pad allows 345 mW P_tot derating - critical for ambient temperatures >70 °C.
Robust ESD tolerance	Class H1B (≥2 kV HBM) per JEDEC JESD22-A114 - eliminates need for external protection in non-industrial I/O interfaces.

Applications

LED Driver Circuit

Microcontroller GPIO Expander

Use Scenario: Driving 20 mA–350 mA indicator or status LEDs from 3.3 V or 5 V microcontroller outputs.

IC Role / Device Role / Timing Role: NPN switch configured in common-emitter mode, sinking current from LED anode to ground.

Use Value: Verified V_CE(sat) ≤ 200 mV at I_C = 20 mA / I_B = 2 mA ensures >95% LED forward voltage utilization and minimal self-heating.

Use Scenario: Extending limited GPIO count by controlling relays, solenoids, or small motors via discrete transistor arrays.

IC Role / Device Role / Timing Role: Low-side switch interfacing MCU outputs to inductive loads with flyback diode integration.

Use Value: 45 V V_CEO safely clamps inductive kickback from 24 V solenoids; 1 A I_CM peak rating handles turn-on surge without failure.

DC-DC Converter Feedback

Level Translation Interface

Use Scenario: Biasing optocoupler inputs in isolated buck/boost feedback loops operating at ≤1 MHz switching frequency.

IC Role / Device Role / Timing Role: Linear amplifier stage converting error amplifier output into optocoupler LED drive current.

Use Value: 100 MHz f_T and stable h_FE over temperature support accurate analog current mirroring with <5% gain drift from –40 °C to 125 °C.

Use Scenario: Translating 1.8 V logic signals to 5 V or 12 V domains in mixed-voltage sensor subsystems.

IC Role / Device Role / Timing Role: Active pull-up/pull-down switch enabling bidirectional level shifting without dedicated ICs.

Use Value: Fast turn-on/off times (<100 ns) and low C_c (3 pF) preserve signal integrity up to 10 MHz clock rates in timing-critical paths.

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
BC817-25,115	Same electrical specs and SOT23 package; differs only in tape-and-reel packaging (10,000 pcs/reel vs. 3,000 pcs/reel for ,235).	No functional difference; identical use in circuit design and layout.	Select ,115 for high-volume automated assembly requiring larger reel quantities.
MMBT3904LT1G	h_FE = 100–300 (lower max gain); V_CEO = 40 V (5 V lower); R_th(j-a) = 530 K/W (worse thermal performance).	Marginally lower drive capability in saturated switching; reduced headroom in 40–45 V systems.	Choose only if legacy MMBT3904 footprint reuse is mandatory and gain margin ≥200 suffices.

Compared with BC817-25,235, the ,115 variant offers identical electrical behavior but optimized for high-throughput SMT lines, while MMBT3904LT1G trades gain and voltage headroom for broader second-source availability - making BC817-25,235 preferable where 160–400 h_FE consistency and 45 V robustness are design-critical.

Availability

BC817-25,235 is available at Aetrix Electronics and suitable for LED driver circuits, microcontroller GPIO expansion, DC-DC converter feedback networks, and level translation interfaces requiring stable component supply across industrial control, consumer electronics, and automotive body electronics programs.

Supply support for BC817-25,235 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-grade components.

The BC817 series belongs to Nexperia's general-purpose transistor product line, engineered for cost-sensitive, space-constrained applications demanding predictable gain, low saturation voltage, and robust thermal performance on standard PCBs.

FAQ

What is the exact h_FE range for BC817-25,235 at I_C = 100 mA?

The BC817-25,235 is binned to deliver DC current gain (h_FE) between 160 and 400 when measured at V_CE = 1 V and I_C = 100 mA, with Tamb = 25 °C. This range is guaranteed per datasheet Table 2 and confirmed across production lots - no additional test screening is required to achieve this specification.

Can BC817-25,235 replace BC817-40 in a circuit designed for higher gain?

No - BC817-40 has h_FE = 250–600, while BC817-25,235 is limited to 160–400. In bias-sensitive amplifier stages or low-base-drive switching applications, substituting BC817-25,235 may cause incomplete saturation or gain-dependent instability. Verify I_B margin and V_CE(sat) under actual load conditions before substitution.

Is BC817-25,235 qualified for automotive applications?

No - per Nexperia's revision history (Rev. 8, July 2022), the BC817 series is explicitly marked "non-automotive qualified" and lacks AEC-Q101 stress testing. For automotive use, select the BC817-Q series (e.g., BC817-25Q), which undergoes extended temperature cycling, humidity testing, and failure analysis per automotive standards.

What is the maximum allowable PCB copper area for optimal thermal performance?

With a 1 cm² copper pad connected to the collector (Pin 3), BC817-25,235 achieves R_th(j-a) = 362 K/W and P_tot = 345 mW at Tamb ≤ 25 °C. Increasing pad size beyond 1 cm² yields diminishing returns; thermal simulation shows <5% improvement in junction temperature with 2 cm², confirming 1 cm² as the practical design optimum.

BC817-25,235 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:: 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:: 250 mW

Frequency - Transition:: 100MHz

Operating Temperature:: 150°C (TJ)

Grade:: Automotive

Qualification:: AEC-Q101

Mounting Type:: Surface Mount

Supplier Device Package:: TO-236AB

BC817-25,235 FAQ

1.How can I place an order for BC817-25,235 through Aetrix?

Please submit a Request for Quotation (RFQ) for BC817-25,235 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 BC817-25,235 reliable?

The price and inventory of BC817-25,235 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC817-25,235 is usually 5 days.

3.What payment methods are accepted for BC817-25,235?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC817-25,235 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC817-25,235?

BC817-25,235 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC817-25,235 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 BC817-25,235?

For technical support, including BC817-25,235 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC817-25,235 requirements.

6.How does Aetrix verify that BC817-25,235 is sourced from the original manufacturer or authorized distributors?

All BC817-25,235 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 BC817-25,235 meets industry standards.

7.What is the process for return or replacement of BC817-25,235?

All BC817-25,235 units undergo pre-shipment inspection (PSI). If there is an issue with BC817-25,235, 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 BC817-25,235 part is unused and in its original packaging.

Return procedure for BC817-25,235:

1.Submit a request within 90 days.

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

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