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

onsemi TIP120

Name: TIP120
Brand: onsemi
SKU: TIP120
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: TIP120

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-220-3

Datasheet:: TIP120.pdf

Description:: TRANS NPN DARL 60V 5A TO-220-3

Quantity:: RFQ Add To RFQ list

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Product details

Overview

TIP120 from ON Semiconductor is an NPN epitaxial Darlington transistor optimized for medium-power linear and switching applications, featuring 60 V V_CEO, 5 A DC collector current, 2.0 V V_CE(sat) at 3 A/12 mA drive, and TO-220 package with integrated base-emitter resistors (8 kΩ/0.12 kΩ). It serves as a high-gain power switch in motor drivers, lamp dimmers, and relay interfaces.

For engineers reviewing the TIP120 datasheet, pinout, applications, or equivalent options, key selection criteria include its 60 V blocking capability, 1000 minimum h_FE at 3 A, saturation voltage under defined drive conditions, thermal derating above 25°C case temperature, and compatibility with standard TO-220 heatsinking footprints.

Technical Context

The TIP120 integrates two NPN transistors in Darlington configuration with on-chip base-emitter resistors (R1 ≈ 8 kΩ, R2 ≈ 0.12 kΩ), enabling direct TTL/CMOS logic-level drive without external base resistors. Its structure delivers high DC current gain (h_FE ≥ 1000) while maintaining V_CE(sat) ≤ 2.0 V at IC = 3 A and IB = 12 mA.

Designed for operation up to 150°C junction temperature, it exhibits 0.5 mA ICEO at V_CE = 30 V and IB = 0, and 200 pF Cob at V_CB = 10 V, f = 0.1 MHz - parameters critical for switching speed and thermal stability in inductive load control.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	60 V - maximum continuous collector-emitter voltage before breakdown; defines safe operating range for 48 V DC systems.
I_C (DC)	5 A - steady-state collector current capacity; supports loads such as 12 V/24 V solenoids and small DC motors.
h_FE	≥1000 at IC = 0.5 A and 3 A - enables low-base-drive switching; reduces driver-stage component count.
V_CE(sat)	2.0 V at IC = 3 A, IB = 12 mA - determines conduction loss and heat generation during on-state operation.
P_C (T_C = 25°C)	65 W - maximum dissipation with adequate heatsinking; requires thermal interface design per derating curve.
C_ob	200 pF at V_CB = 10 V - impacts turn-off speed and EMI in PWM-driven inductive loads.

Pinout & Package

Package: TO-220 3L (Single Gauge), through-hole, thermally enhanced plastic case with metal tab electrically connected to collector. Mounting hole allows mechanical attachment to heatsink.

Pin/Terminal	Circuit Role	Design Meaning
1 (Base)	Input control terminal	Accepts TTL/CMOS-compatible drive; internal 8 kΩ resistor pulls base toward emitter when un-driven.
2 (Collector)	High-current output node	Connected to metal tab; must be isolated from heatsink unless circuit ground reference permits.
3 (Emitter)	Current return path	Low-side switching reference; internal 0.12 kΩ resistor provides emitter degeneration for stability.

Key Features

Feature	Design Value
Integrated Darlington pair with bias resistors	Eliminates need for external base resistor network; simplifies PCB layout and reduces BOM count.
High DC current gain (h_FE ≥ 1000)	Enables direct drive from microcontroller GPIO pins without additional transistor stages.
65 W power dissipation at T_C = 25°C	Supports robust thermal management in industrial control enclosures with forced-air or passive heatsinking.
150°C maximum junction temperature	Permits operation in high-ambient environments such as automotive engine compartments or enclosed power supplies.

Applications

DC Motor Control	Lamp & LED Dimming
Use Scenario: Controlling bidirectional brushed DC motors in robotics or automated valves using H-bridge half-bridge configurations. IC Role / Device Role / Timing Role: Low-side NPN Darlington switch providing 5 A peak current handling and fast turn-on with logic-level input. Use Value: High h_FE ensures full saturation with minimal MCU GPIO current, reducing driver complexity and board space.	Use Scenario: Phase-angle or PWM dimming of incandescent lamps and high-power LED strings in architectural lighting systems. IC Role / Device Role / Timing Role: Main power switch in TRIAC-trigger or PWM-output stage, handling 60 V transient spikes and 5 A RMS load current. Use Value: 60 V V_CEO and 2.0 V V_CE(sat) minimize conduction loss and enable efficient thermal design at 12–24 V supply rails.
Relay & Solenoid Drivers	Industrial PLC Output Modules
Use Scenario: Replacing electromechanical relays in programmable logic controllers for 24 V DC solenoid actuation. IC Role / Device Role / Timing Role: Solid-state replacement for relay contacts, delivering zero-bounce switching and >100 kHz operational lifetime. Use Value: Integrated base-emitter resistors prevent latch-up during transient noise events, improving system reliability in noisy factory environments.	Use Scenario: Discrete output stage in DIN-rail mounted PLC modules driving mixed 12/24 V DC field devices. IC Role / Device Role / Timing Role: Final-stage power switch with built-in current limiting and thermal shutdown coordination via external sensing. Use Value: TO-220 package allows standardized heatsink mounting across multiple I/O channels, simplifying mechanical design and serviceability.

DC Motor Control

Lamp & LED Dimming

Use Scenario: Controlling bidirectional brushed DC motors in robotics or automated valves using H-bridge half-bridge configurations.

IC Role / Device Role / Timing Role: Low-side NPN Darlington switch providing 5 A peak current handling and fast turn-on with logic-level input.

Use Value: High h_FE ensures full saturation with minimal MCU GPIO current, reducing driver complexity and board space.

Use Scenario: Phase-angle or PWM dimming of incandescent lamps and high-power LED strings in architectural lighting systems.

IC Role / Device Role / Timing Role: Main power switch in TRIAC-trigger or PWM-output stage, handling 60 V transient spikes and 5 A RMS load current.

Use Value: 60 V V_CEO and 2.0 V V_CE(sat) minimize conduction loss and enable efficient thermal design at 12–24 V supply rails.

Relay & Solenoid Drivers

Industrial PLC Output Modules

Use Scenario: Replacing electromechanical relays in programmable logic controllers for 24 V DC solenoid actuation.

IC Role / Device Role / Timing Role: Solid-state replacement for relay contacts, delivering zero-bounce switching and >100 kHz operational lifetime.

Use Value: Integrated base-emitter resistors prevent latch-up during transient noise events, improving system reliability in noisy factory environments.

Use Scenario: Discrete output stage in DIN-rail mounted PLC modules driving mixed 12/24 V DC field devices.

IC Role / Device Role / Timing Role: Final-stage power switch with built-in current limiting and thermal shutdown coordination via external sensing.

Use Value: TO-220 package allows standardized heatsink mounting across multiple I/O channels, simplifying mechanical design and serviceability.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
BD679	Lower V_CEO (80 V), lower h_FE (750 min), TO-126 package	Less suitable for 60 V inductive flyback; limited heatsinking capability	Prefer TIP120 where higher gain and TO-220 thermal performance are required
TIP102	Same V_CEO (60 V), same package, but h_FE = 500 min and higher V_CE(sat) (3.0 V)	Requires stronger base drive; less efficient at high current	Select TIP120 when lower saturation voltage and higher gain justify cost premium

Compared with BD679 and TIP102, the TIP120 delivers superior current gain and lower saturation voltage in the same TO-220 footprint, making it optimal for thermally constrained, high-reliability switching where drive current is limited and conduction loss must be minimized.

Availability

TIP120 is available at Aetrix Electronics and suitable for DC motor control, industrial relay replacement, and lamp dimming applications requiring stable component supply and long-term manufacturing continuity.

Supply support for TIP120 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 (now part of onsemi) is a global semiconductor supplier specializing in power management, analog, sensor, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.

The TIP120 belongs to the legacy bipolar power transistor product line designed specifically for robust, cost-effective discrete switching in industrial controls, power supplies, and electromechanical interface circuits.

FAQ

What is the maximum continuous collector current rating for the TIP120?

The TIP120 has a rated DC collector current (I_C) of 5 A at T_C = 25°C. This rating assumes proper heatsinking; actual usable current decreases with rising case temperature per the 0.5 W/°C derating curve shown in Figure 5 of the official datasheet. Pulse current capability reaches 8 A for short durations (≤300 μs, duty cycle ≤2%).

Does the TIP120 require an external base resistor when driven by a microcontroller?

No - the TIP120 incorporates internal base-emitter resistors (≈8 kΩ and ≈0.12 kΩ), enabling direct connection to 3.3 V or 5 V logic outputs without external biasing components. This eliminates risk of unintended turn-on due to floating base and simplifies interface design compared to standard bipolar transistors.

What is the collector-emitter saturation voltage (V_CE(sat)) of the TIP120 under typical operating conditions?

The TIP120 specifies V_CE(sat) ≤ 2.0 V at I_C = 3 A and I_B = 12 mA, and ≤ 4.0 V at I_C = 5 A and I_B = 20 mA. These values reflect actual conduction losses under defined drive conditions and are critical for calculating thermal rise and efficiency in switching applications.

Can the TIP120 be used in place of the TIP121 or TIP122?

The TIP120 is not a drop-in replacement for TIP121 or TIP122 due to lower voltage ratings: TIP120 supports only 60 V V_CEO/V_CBO, whereas TIP121 and TIP122 support 80 V and 100 V respectively. Substitution is acceptable only if the application's maximum collector voltage remains ≤60 V and all other parameters meet design requirements.

Is the metal tab on the TIP120 package electrically connected, and to which terminal?

Yes - the metal tab of the TIP120 in TO-220 package is internally connected to the collector terminal (Pin 2). When mounted to a heatsink, electrical isolation (e.g., mica washer + insulating sleeve) is required unless the heatsink is referenced to the collector potential in the circuit.

TIP120 Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-220-3

Packaging:: Bulk

Product Status:: Obsolete

Transistor Type:: NPN - Darlington

Current - Collector (Ic) (Max):: 5 A

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

Vce Saturation (Max) @ Ib, Ic:: 4V @ 20mA, 5A

Current - Collector Cutoff (Max):: 500µA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 1000 @ 3A, 3V

Power - Max:: 2 W

Frequency - Transition:: -

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220-3

TIP120 FAQ

1.How can I place an order for TIP120 through Aetrix?

Please submit a Request for Quotation (RFQ) for TIP120 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 TIP120 reliable?

The price and inventory of TIP120 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TIP120 is usually 5 days.

3.What payment methods are accepted for TIP120?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TIP120 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for TIP120?

TIP120 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your TIP120 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 TIP120?

For technical support, including TIP120 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TIP120 requirements.

6.How does Aetrix verify that TIP120 is sourced from the original manufacturer or authorized distributors?

All TIP120 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 TIP120 meets industry standards.

7.What is the process for return or replacement of TIP120?

All TIP120 units undergo pre-shipment inspection (PSI). If there is an issue with TIP120, 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 TIP120 part is unused and in its original packaging.

Return procedure for TIP120:

1.Submit a request within 90 days.

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

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