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 2N3055H

Name: 2N3055H
Brand: onsemi
SKU: 2N3055H
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: 2N3055H

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-204AA, TO-3

Datasheet:: 2N3055H.pdf

Description:: TRANS NPN 60V 15A TO204

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:4,216

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

Product details

Overview

2N3055H from onsemi is an NPN silicon power transistor in TO-204AA (TO-3) metal package, rated for 60 V_CEO, 15 A_C, and 115 W at T_C = 25°C, with h_FE = 20–70 at I_C = 4 A and V_CE = 4 V - used in linear power supplies, audio amplifiers, and motor control switching circuits.

For engineers reviewing the 2N3055H datasheet, pinout, applications, or equivalent options, key selection criteria include safe operating area (SOA) integrity at high I_C/V_CE combinations, thermal resistance (R_JC = 1.52 °C/W), saturation voltage (V_CE(sat) ≤ 1.1 V @ I_C = 4 A), and second-breakdown immunity under pulsed loads.

Technical Context

The 2N3055H operates as a single-ended, high-current NPN bipolar junction transistor optimized for linear and switching operation in discrete power stages. It features a rugged silicon die with excellent second-breakdown performance (I_s/b = 2.87 A @ V_CE = 40 V, t = 1 s) and thermally limited SOA up to 115 W at case temperature 25°C.

Its DC current gain varies from 20 to 70 depending on collector current and junction temperature, while small-signal f_T is 2.5 MHz (I_C = 0.5 A, V_CE = 10 V), supporting medium-frequency amplifier and regulator designs where wide SOA and robust thermal handling are prioritized over RF performance.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	60 Vdc - maximum collector-emitter voltage before breakdown with base open; defines upper rail limit in linear regulators and Class-AB amplifiers.
I_C (cont.)	15 Adc - continuous collector current rating; supports high-power output stages without forced cooling at moderate duty cycles.
P_D @ T_C=25°C	115 W - total power dissipation capability at case temperature 25°C; requires large heatsink for sustained operation near rating.
h_FE	20–70 @ I_C=4 A - DC current gain range determines required base drive current (e.g., ~57–200 mA for 4 A output).
V_CE(sat)	≤1.1 V @ I_C=4 A, I_B=400 mA - low saturation voltage minimizes conduction loss in switching applications like relay drivers.
R_JC	1.52 °C/W - junction-to-case thermal resistance; enables accurate heatsink sizing using measured case temperature.
f_T	2.5 MHz - transition frequency limits usable bandwidth in small-signal amplification but suffices for audio and SMPS error amplifiers.

Pinout & Package

2N3055H uses the TO-204AA (TO-3) metal-can package with three terminals: Collector (case), Base (center lead), and Emitter (right lead when viewed with leads down and tab facing outward). The metal case is electrically connected to the collector, requiring insulated mounting hardware in most applications.

Pin/Terminal	Circuit Role	Design Meaning
Case (Metal Can)	Collector	Electrically active collector terminal; must be isolated from chassis/heat sink unless circuit topology permits common-collector configuration.
Center Lead	Base	Control input requiring sufficient drive current (≥400 mA for full 4 A saturation); sensitive to ESD and layout parasitics.
Right Lead (viewed with tab up)	Emitter	Current return path; often tied to ground or negative rail; low-impedance connection critical for stability in high-gain amplifiers.

Key Features

Feature	Design Value
Excellent Safe Operating Area (SOA)	Defined up to 115 W at 25°C case temperature with validated second-breakdown limits - enables reliable operation in unregulated linear supplies and analog output stages.
High V_CER = 70 V	Supports operation with base-emitter resistor biasing under transient overvoltage conditions without latch-up or avalanche failure.
Low R_JC = 1.52 °C/W	Allows efficient heat transfer to external heatsink; reduces thermal runaway risk in parallel configurations when properly derated.
Pb-Free Option Available	2N3055G variant meets RoHS requirements; 2N3055H is standard leaded version - both share identical electrical and thermal specs.
JEDEC-Registered Device	Fully compliant with JEDEC TO-204AA mechanical and electrical standards - ensures interchangeability across qualified manufacturers.

Applications

Linear Power Supply Regulation	Audio Power Amplifier Output Stage
Use Scenario: Discrete series pass element in adjustable 0–30 V, 5 A bench power supply with foldback current limiting. IC Role / Device Role / Timing Role: NPN series pass transistor controlling output voltage via base drive from error amplifier; handles full load current and dissipates variable power based on input-output differential. Use Value: High SOA and 115 W dissipation allow stable regulation across wide line/load transients without thermal shutdown or second-breakdown failure.	Use Scenario: Complementary push-pull output stage in 50 W RMS Class-AB audio amplifier driving 4 Ω speakers. IC Role / Device Role / Timing Role: High-current NPN output device delivering peak positive half-cycle current; paired with MJ2955 PNP for full waveform reproduction. Use Value: h_FE consistency across temperature and low V_CE(sat) reduce crossover distortion and improve thermal tracking in biased complementary pairs.
Motor Speed Control (DC Brushed)	Industrial Relay/Contactor Driver
Use Scenario: Single-transistor PWM switch controlling 12 V, 8 A DC brushed motor in factory automation actuator. IC Role / Device Role / Timing Role: High-current switching element turning motor on/off at 1–5 kHz; operated in saturation/cutoff to minimize switching losses. Use Value: V_CE(sat) ≤ 1.1 V at 4 A keeps conduction loss below 4.4 W, enabling compact heatsinking even at 100% duty cycle.	Use Scenario: Direct-drive interface between microcontroller GPIO and 24 VDC industrial relay coil (120 mW, 200 Ω). IC Role / Device Role / Timing Role: General-purpose power switch providing >10× coil current gain to ensure reliable relay pull-in with minimal MCU sourcing. Use Value: Robust V_CEO = 60 V withstands inductive kickback spikes up to 70 V (V_CER), eliminating need for external flyback diode in many cases.

Linear Power Supply Regulation

Audio Power Amplifier Output Stage

Use Scenario: Discrete series pass element in adjustable 0–30 V, 5 A bench power supply with foldback current limiting.

IC Role / Device Role / Timing Role: NPN series pass transistor controlling output voltage via base drive from error amplifier; handles full load current and dissipates variable power based on input-output differential.

Use Value: High SOA and 115 W dissipation allow stable regulation across wide line/load transients without thermal shutdown or second-breakdown failure.

Use Scenario: Complementary push-pull output stage in 50 W RMS Class-AB audio amplifier driving 4 Ω speakers.

IC Role / Device Role / Timing Role: High-current NPN output device delivering peak positive half-cycle current; paired with MJ2955 PNP for full waveform reproduction.

Use Value: h_FE consistency across temperature and low V_CE(sat) reduce crossover distortion and improve thermal tracking in biased complementary pairs.

Motor Speed Control (DC Brushed)

Industrial Relay/Contactor Driver

Use Scenario: Single-transistor PWM switch controlling 12 V, 8 A DC brushed motor in factory automation actuator.

IC Role / Device Role / Timing Role: High-current switching element turning motor on/off at 1–5 kHz; operated in saturation/cutoff to minimize switching losses.

Use Value: V_CE(sat) ≤ 1.1 V at 4 A keeps conduction loss below 4.4 W, enabling compact heatsinking even at 100% duty cycle.

Use Scenario: Direct-drive interface between microcontroller GPIO and 24 VDC industrial relay coil (120 mW, 200 Ω).

IC Role / Device Role / Timing Role: General-purpose power switch providing >10× coil current gain to ensure reliable relay pull-in with minimal MCU sourcing.

Use Value: Robust V_CEO = 60 V withstands inductive kickback spikes up to 70 V (V_CER), eliminating need for external flyback diode in many cases.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
2N3055G	Pb-free variant of same die and TO-204AA package; identical max ratings, SOA, and electrical specs.	No functional difference; selected only when RoHS compliance is mandatory for final product certification.	Choose 2N3055G for new designs targeting EU/China RoHS markets; 2N3055H remains valid for legacy or non-regulated applications.
MJ15003	Higher V_CEO = 150 V, higher h_FE = 30–120, lower R_JC = 1.0 °C/W, but same TO-3 package footprint.	Better suited for high-voltage linear regulators (>80 V input) and high-fidelity audio where tighter h_FE tolerance matters.	Select MJ15003 when V_IN exceeds 70 V or when improved thermal margin and gain consistency justify cost premium over 2N3055H.

Compared with 2N3055G and MJ15003, the 2N3055H offers the lowest-cost, industry-standard solution for 60 V-class power switching and amplification - retaining full compatibility with decades of proven designs while delivering predictable SOA-limited reliability under real-world thermal stress.

Availability

2N3055H is available at Aetrix Electronics and suitable for linear power supplies, audio amplifier output stages, and industrial relay drivers requiring stable component supply and long-term obsolescence resilience.

Supply support for 2N3055H 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power, analog, sensor, and connectivity solutions for automotive, industrial, cloud, and IoT applications.

The 2N3055H belongs to onsemi's legacy discrete power transistor family - designed for robust, high-reliability linear and switching applications where proven SOA, thermal stability, and JEDEC-standard interoperability are essential.

FAQ

What is the maximum continuous collector current rating for the 2N3055H?

The 2N3055H has a maximum continuous collector current (I_C) rating of 15 A at case temperature T_C = 25°C. This rating decreases with rising case temperature per the derating curve (0.657 W/°C), and actual usable current depends on heatsink efficiency and ambient conditions. For reliable long-term operation, design margins should keep peak I_C below 12 A under typical thermal constraints.

Is the 2N3055H pin-compatible with the MJ2955 PNP transistor?

Yes - the 2N3055H and MJ2955 share identical TO-204AA (TO-3) mechanical packaging and terminal arrangement (case = collector/emitter, center = base, right = emitter/collector), enabling direct physical substitution in complementary circuits. However, they are not electrically interchangeable: 2N3055H is NPN, MJ2955 is PNP, so polarity and biasing must be reversed in circuit layout.

Does the 2N3055H require a heatsink in all applications?

Yes - the 2N3055H must be mounted to an appropriately sized heatsink in any application where power dissipation exceeds ~2–3 W. With R_JC = 1.52 °C/W and maximum junction temperature of +200°C, even modest dissipation (e.g., 10 W) raises junction temperature significantly above ambient without thermal management. Insulated mounting hardware is required due to collector-connected case.

What is the safe operating area (SOA) limitation for the 2N3055H at 100 V_CE?

The 2N3055H is not rated for 100 V_CE operation: its absolute maximum V_CEO is 60 Vdc and V_CER is 70 Vdc. At V_CE = 100 V, the device exceeds its breakdown rating and risks catastrophic failure. SOA curves in the datasheet only extend to 60 V - operation beyond this violates JEDEC limits and voids reliability guarantees.

Can the 2N3055H be used in switching-mode power supply (SMPS) primary-side switches?

No - the 2N3055H is not optimized for high-frequency switching. Its f_T = 2.5 MHz and relatively slow turn-on/turn-off times (not specified but implied by construction) result in excessive switching losses above ~20 kHz. It is intended for linear regulation and low-frequency (<5 kHz) PWM applications; modern SMPS use MOSFETs or faster BJTs like MJE13009.

2N3055H Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-204AA, TO-3

Packaging:: Tray

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 15 A

Voltage - Collector Emitter Breakdown (Max):: 60 V

Vce Saturation (Max) @ Ib, Ic:: 3V @ 3.3A, 10A

Current - Collector Cutoff (Max):: 700µA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 20 @ 4A, 4V

Power - Max:: 115 W

Frequency - Transition:: 2.5MHz

Operating Temperature:: -65°C ~ 200°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-204 (TO-3)

2N3055H FAQ

1.How can I place an order for 2N3055H through Aetrix?

Please submit a Request for Quotation (RFQ) for 2N3055H 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 2N3055H reliable?

The price and inventory of 2N3055H are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 2N3055H is usually 5 days.

3.What payment methods are accepted for 2N3055H?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 2N3055H transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for 2N3055H?

2N3055H orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 2N3055H 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 2N3055H?

For technical support, including 2N3055H datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 2N3055H requirements.

6.How does Aetrix verify that 2N3055H is sourced from the original manufacturer or authorized distributors?

All 2N3055H 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 2N3055H meets industry standards.

7.What is the process for return or replacement of 2N3055H?

All 2N3055H units undergo pre-shipment inspection (PSI). If there is an issue with 2N3055H, 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 2N3055H part is unused and in its original packaging.

Return procedure for 2N3055H:

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…