Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

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

onsemi BC337

Name: BC337
Brand: onsemi
SKU: BC337
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: BC337

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-226-3, TO-92-3 (TO-226AA)

Datasheet:: BC337.pdf

Description:: TRANS NPN 45V 0.8A TO-92-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:7,032

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

BC337 from ON Semiconductor is an NPN epitaxial silicon transistor in TO-92 package, rated for 45 V V_CEO, 800 mA I_C, 625 mW P_D, with h_FE range 250–630 (BC337-40 variant), and f_T = 100 MHz - used in low-power amplifier and switching stages of consumer audio, power supply control, and signal conditioning circuits.

For engineers reviewing the BC337 datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, TO-92 terminal mapping, real-world use cases in AF driver stages and low-power output circuits, and validated alternative transistors with documented h_FE and voltage rating differences.

Technical Context

The BC337 operates as a general-purpose bipolar junction transistor optimized for linear amplification and saturated switching. Its DC current gain (h_FE) is binned into three classes (16/25/40), with BC33740TA specifying the highest h_FE group (250–630 at I_C = 100 mA). It features low V_CE(sat) (0.7 V @ I_C = 500 mA, I_B = 50 mA) and moderate f_T (100 MHz), supporting audio-frequency and low-speed digital switching.

Thermal performance is defined by R_θJA = 200 °C/W on standard FR-4 PCB, limiting continuous power dissipation to 625 mW at 25 °C ambient, derating 5 mW/°C above that. The device shares complementary pairing with BC327 (PNP), enabling push-pull configurations in Class A/B amplifier outputs.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	45 V - Maximum collector-emitter voltage before breakdown under open-base conditions; sets safe operating voltage ceiling in amplifier biasing and switch off-state.
I_C (DC)	800 mA - Continuous collector current limit; defines maximum load drive capability in relay drivers or LED switches.
h_FE (BC337-40)	250–630 - DC current gain range at V_CE = 1 V, I_C = 100 mA; enables predictable base drive sizing for saturation in switching designs.
f_T	100 MHz - Current gain bandwidth product; supports stable small-signal amplification up to ~10 MHz with gain margin.
V_CE(sat)	0.7 V @ I_C = 500 mA, I_B = 50 mA - Low saturation voltage reduces conduction loss and heat generation in switching applications.
P_D	625 mW - Maximum power dissipation at 25 °C ambient; determines heatsinking requirements and duty-cycle limits in pulsed operation.

Pinout & Package

BC337 is housed in a JEDEC TO-92 3-lead plastic package with straight or bent leads, standardized for through-hole mounting and manual prototyping. Pin 1 is Collector, Pin 2 is Base, Pin 3 is Emitter - confirmed across Fairchild/ON Semiconductor datasheets and physical marking diagrams.

Pin/Terminal	Circuit Role	Design Meaning
1 (Collector)	Main current sink terminal	Connected to load or supply rail; carries full collector current; requires thermal consideration due to power dissipation path.
2 (Base)	Control input for current amplification	Receives bias current to regulate collector-emitter conduction; high-impedance node sensitive to noise and leakage.
3 (Emitter)	Current source reference terminal	Typically grounded or connected to emitter resistor for bias stabilization; defines common reference for V_BE and h_FE-based calculations.

Key Features

Feature	Design Value
High h_FE binning (BC337-40)	250–630 gain range ensures consistent base drive requirements across production lots in amplifier feedback networks.
Low V_CE(sat)	0.7 V at 500 mA enables efficient switching in battery-powered loads with minimal voltage drop and heat rise.
Complementary pairing with BC327	Enables matched push-pull output stages in audio preamps and class-B amplifiers without custom matching.
TO-92 mechanical standardization	Ensures compatibility with legacy sockets, breadboards, and automated through-hole assembly equipment.

Applications

Audio Frequency Driver Stage	Low-Power Switching Load Control
Use Scenario: Driving 8 Ω speaker loads in portable radio output stages with single-supply 9 V rails. IC Role / Device Role / Timing Role: NPN transistor configured in common-emitter amplifier mode to deliver 100–300 mW undistorted output. Use Value: High h_FE (250–630) allows simple resistor-biased design with minimal external components and stable gain over temperature.	Use Scenario: Controlling 12 V solenoid valves or indicator LEDs in industrial control panels. IC Role / Device Role / Timing Role: Saturated switch turning on/off loads via microcontroller GPIO with 50 mA base drive. Use Value: V_CE(sat) ≤ 0.7 V minimizes power loss and self-heating during sustained on-state operation.
Linear Voltage Regulator Pass Element	Signal Level Shifting Interface
Use Scenario: Acting as series pass transistor in adjustable 3-terminal regulator circuits powering analog sensors. IC Role / Device Role / Timing Role: Operated in active region to maintain constant output voltage under varying load currents up to 500 mA. Use Value: 45 V V_CEO headroom supports input-to-output differentials up to 35 V while maintaining safe SOA margins.	Use Scenario: Translating 3.3 V logic signals to 5 V or 12 V domains in mixed-voltage microcontroller systems. IC Role / Device Role / Timing Role: Common-emitter level shifter with pull-up resistor on collector and base driven by MCU output. Use Value: f_T = 100 MHz supports clean edge transitions up to ~5 MHz, avoiding timing skew in interface clock domains.

Audio Frequency Driver Stage

Low-Power Switching Load Control

Use Scenario: Driving 8 Ω speaker loads in portable radio output stages with single-supply 9 V rails.

IC Role / Device Role / Timing Role: NPN transistor configured in common-emitter amplifier mode to deliver 100–300 mW undistorted output.

Use Value: High h_FE (250–630) allows simple resistor-biased design with minimal external components and stable gain over temperature.

Use Scenario: Controlling 12 V solenoid valves or indicator LEDs in industrial control panels.

IC Role / Device Role / Timing Role: Saturated switch turning on/off loads via microcontroller GPIO with 50 mA base drive.

Use Value: V_CE(sat) ≤ 0.7 V minimizes power loss and self-heating during sustained on-state operation.

Linear Voltage Regulator Pass Element

Signal Level Shifting Interface

Use Scenario: Acting as series pass transistor in adjustable 3-terminal regulator circuits powering analog sensors.

IC Role / Device Role / Timing Role: Operated in active region to maintain constant output voltage under varying load currents up to 500 mA.

Use Value: 45 V V_CEO headroom supports input-to-output differentials up to 35 V while maintaining safe SOA margins.

Use Scenario: Translating 3.3 V logic signals to 5 V or 12 V domains in mixed-voltage microcontroller systems.

IC Role / Device Role / Timing Role: Common-emitter level shifter with pull-up resistor on collector and base driven by MCU output.

Use Value: f_T = 100 MHz supports clean edge transitions up to ~5 MHz, avoiding timing skew in interface clock domains.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC337-25TA	Lower h_FE range (160–400) and same V_CEO/I_C ratings; identical TO-92 package and pinout.	Suitable where gain consistency is less critical and lower base drive current suffices.	Select when cost sensitivity outweighs need for highest gain stability in amplifier feedback paths.
PN2222A	Higher V_CEO (60 V), lower max h_FE (100–300), same TO-92 package; V_CE(sat) slightly higher (0.8 V).	Better suited for higher-voltage switching (e.g., 48 V telecom supplies) but less optimal for low-noise AF amplification.	Choose when system voltage exceeds 45 V or when legacy PN2222A footprint compatibility is required.

Compared with BC33740TA, BC337-25TA offers reduced gain headroom but tighter binning tolerance for cost-sensitive switching, while PN2222A trades gain and saturation voltage for broader voltage capability - making BC33740TA optimal for precision low-voltage amplification and efficient low-power switching where h_FE > 250 is essential.

Availability

BC337 is available at Aetrix Electronics and suitable for audio frequency driver stages, low-power switching load control, linear voltage regulator pass elements, and signal level shifting interfaces requiring stable component supply and long-term obsolescence management.

Supply support for BC337 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The BC337 belongs to ON Semiconductor's general-purpose bipolar transistor product line, designed for cost-effective, reliable amplification and switching in non-safety-critical commercial and industrial electronics.

FAQ

What is the maximum collector-emitter voltage rating for BC337?

The BC337 has a maximum collector-emitter voltage (V_CEO) rating of 45 V under open-base conditions at T_A = 25 °C. This value is confirmed in the Absolute Maximum Ratings table of the official ON Semiconductor datasheet for BC337/BC338 Rev. 1.5. Exceeding this voltage risks avalanche breakdown and permanent device damage. For BC33740TA specifically, this rating remains unchanged across all h_FE variants.

How does BC33740TA differ from BC337-25TA?

BC33740TA and BC337-25TA share identical package (TO-92), pinout, and absolute maximum ratings, but differ in DC current gain (h_FE): BC33740TA is binned to 250–630 at I_C = 100 mA, while BC337-25TA is binned to 160–400. This makes BC33740TA preferable for high-gain amplifier stages where base drive current must be minimized, whereas BC337-25TA suits cost-sensitive switching applications with looser gain tolerance.

Is BC337 suitable for audio amplifier applications?

Yes, BC337 is explicitly qualified for audio frequency driver stages and low-power output stages per its official datasheet features. Its f_T of 100 MHz, low noise characteristics, and stable h_FE across temperature make BC337 well-suited for preamplifier and driver circuits in portable radios and intercom systems - especially the BC33740TA variant, which provides higher gain consistency for feedback loop stability.

What is the thermal resistance of BC337 in TO-92 package?

The BC337 has a junction-to-ambient thermal resistance (R_θJA) of 200 °C/W when mounted on a standard FR-4 PCB (76 mm × 114 mm × 1.57 mm) with minimum land pattern. This value is specified in the Thermal Characteristics section of the BC337/BC338 datasheet. At 25 °C ambient, this limits continuous power dissipation to 625 mW; derating is 5 mW/°C above that temperature.

Does BC337 have a complementary PNP counterpart?

Yes, BC337 has a direct complementary PNP counterpart: BC327. Both devices share identical package (TO-92), pinout (C-B-E), voltage/current ratings, and thermal specifications, enabling matched push-pull configurations in Class B and AB amplifier outputs. This pairing is explicitly stated in the "Features" section of the BC337/BC338 datasheet and supported across ON Semiconductor's product documentation.

BC337 Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-226-3, TO-92-3 (TO-226AA)

Packaging:: Bulk

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 800 mA

Voltage - Collector Emitter Breakdown (Max):: 45 V

Vce Saturation (Max) @ Ib, Ic:: 700mV @ 50mA, 500mA

Current - Collector Cutoff (Max):: 100nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 100 @ 100mA, 1V

Power - Max:: 625 mW

Frequency - Transition:: 210MHz

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92-3

BC337 FAQ

1.How can I place an order for BC337 through Aetrix?

Please submit a Request for Quotation (RFQ) for BC337 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 BC337 reliable?

The price and inventory of BC337 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC337 is usually 5 days.

3.What payment methods are accepted for BC337?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC337 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC337?

BC337 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC337 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 BC337?

For technical support, including BC337 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC337 requirements.

6.How does Aetrix verify that BC337 is sourced from the original manufacturer or authorized distributors?

All BC337 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 BC337 meets industry standards.

7.What is the process for return or replacement of BC337?

All BC337 units undergo pre-shipment inspection (PSI). If there is an issue with BC337, 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 BC337 part is unused and in its original packaging.

Return procedure for BC337:

1.Submit a request within 90 days.

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

Tech Hub

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…