A Complete Guide to TIP120 NPN Darlington Transistor
06 December 2023
Ⅰ. What is a Darlington transistor?
Ⅲ. TIP120 symbol, footprint and pin configuration
Ⅳ. What are the features of TIP120 Darlington transistor?
Ⅴ. How does the TIP120 Darlington transistor work?
Ⅵ. How to use TIP120 Darlington transistor?
Ⅶ. Technical parameters of TIP120 Darlington transistor
Ⅷ. What are the applications of TIP120 Darlington transistor?
Darlington transistor arrangements encompass multiple transistors designed to operate comparably to a single transistor, incorporating base, emitter, and collector elements. Among the well-known NPN power Darlington transistors is the TIP120. This article will provide an overview of its features, technical parameters, working principle, and usage guidelines.
Darlington transistor was invented by American electrical engineer and inventor Sidney Darlington in 1953. It is also known as a compound tube. It connects two transistors in series to form an equivalent new transistor. The amplification of this equivalent transistor is the product of the original two transistors, and is therefore characterized by ultra-high amplification. Typically, Darlington tubes are used to amplify very small signals in high-sensitivity amplification circuits, such as high-power switching circuits. In electronics circuit design, Darlington connection is commonly used in power amplifiers and voltage regulators.
The TIP120 is a through-hole complementary power Darlington transistor in a TO-220 package that is widely used for general purpose amplification and low speed switching purposes. This array of Darlington transistors has a maximum emitter-base voltage of 5V and operates over a temperature range of -65°C to 150°C. The TIP120 is packaged in tube to provide additional protection by storing loose parts in the outer tube. Specifically, the product is packaged with parts placed in a tubular enclosure, which further enhances its protective properties.
The device is capable of switching loads up to 60V at a continuous collector source current of 5A with a minimum current amplification factor (hFE) of 1000, and is fabricated in planar technology with a "base island" layout and monolithic Darlington configuration for excellent high gain performance and very low saturation voltage.
Replacements and equivalents:
• BDW43
• BU807
• MJF122
• TIP110
• TIP120TU
• TIP120G
• 2N6388G
The symbol, footprint and pin configuration of TIP120 are shown in the figure below.
Among them, TIP120 has three pins, namely base, collector and emitter.
Pin 1 (Base): The base is the trigger for the transistor.
Pin 2 (Collector): Current flows through the collector.
Pin 3 (Emitter): Current flows through the emitter.
• It comes in a TO-220 package and has the characteristics of a through-hole complementary power Darlington transistor.
• It has excellent high gain performance and extremely low saturation voltage.
• TIP120 has larger voltage and current and is typically designed for higher power electronic circuits.
• TIP120 also has lower power consumption and higher voltage resistance.
In the TIP120, the output signal of the first transistor is further amplified by the second transistor to provide a higher overall current gain. This unique Darlington structure enables the TIP120 to exhibit excellent performance in general amplification applications. When the TIP120's base receives an input signal, the first transistor immediately amplifies it. A second transistor then further amplifies this signal, allowing the TIP120 to provide sufficient output current. This amplification allows the TIP120 to provide larger output current while maintaining a low voltage drop.
TIP120 can be applied to various switching and amplification related scenarios. When used as a switch, it requires only 120mA base current to fully saturate and drive a 5000mA or 5A load. With up to 5A of current, it can drive switches such as high-power LEDs, LED bulbs, high-power relays, or even an entire circuit or a completely independent device. When used as an amplifier, the TIP120 can amplify small amounts of audio and drive high-power speakers with any additional circuitry required. Additionally, it can be used in amplifier stages and preamplifiers. Its emitter-base voltage value makes it ideal for use with microcontrollers and other devices to drive loads up to 5A.
Manufacturer: STMicroelectronics
Package / Case: TO-220-3
Packaging: Tube
Length: 10.4 mm
Width: 4.6mm
Height: 9.15mm
Part Status: Active
Configuration: Single
Transistor Polarity: NPN
Operating Temperature: -65°C ~ 150°C
Mounting Style: Through Hole
Pin Count: 3
Product Type: Darlington Transistors
Maximum Collector Cut-off Current: 200 uA
Maximum DC Collector Current: 5 A
Emitter- Base Voltage VEBO: 5 V
Collector- Emitter Voltage VCEO Max: 60 V
• Inverter: TIP120 can be used to build an inverter circuit to convert DC power to AC power.
• Switching power supply: TIP120 can be used as a switching element in a switching power supply to control the flow of current through the load. By applying appropriate voltage to the base, we can control the on and off states of TIP120 to achieve switching control of the load.
• Audio amplification: In audio systems, TIP120 is usually used to amplify audio signals. By connecting the base, emitter and ground wires of the TIP120, it can amplify the audio signal and then output it through the collector.
• Temperature control: It uses TIP120 in temperature control systems to achieve temperature regulation by controlling the current of the heating element.
• Motor control: In motor drive systems, TIP120 can be used as a power amplifier to amplify weak control signals and drive the motor. For example, in DC motor driving, we can connect the base of TIP120 with Arduino or other microcontroller. By adjusting the duty cycle of the PWM signal, we can effectively control the motor speed.
Frequently Asked Questions
1. Is TIP120 a Mosfet?
The Tip120 is not a mosfet, but a Darlington transistor. Mosfets are either n-chanel or p-chanel.
2. What is a TIP120?
The TIP120 is an NPN Power Darlington Transistor. It can be used with an Arduino to drive motors, turn lights on, and drive other high power gadgets. The TIP120 acts as a power broker or gatekeeper between the Arduino realm and the high power realm composed of the PC fan and its battery pack.
3. How does a TIP120 transistor work?
TIP120 comes with a Darlington pair in which two transistors are connected in such a way, the current amplified by the one transistor is being amplified further by the other transistor. This configuration features a much higher current gain as compared to if each transistor is taken separately.
4. How to use TIP120 with Arduino?
Connect pin 9 on the Arduino to the base pin of the TIP120. If you are looking at the transistor so that the metal tab is facing away from you, the base pin is on the left side of the transistor. This is the pin that will control open or close.
5. What is the difference between TIP120 and TIP122?
TIP120 is a 60V 5A NPN Darlington with an Emitter-Base Voltage of 5V and Base Current (DC) of 120 mA. TIP121 and TIP122 are the 80V and 100V versions. The TIP122 will work as a replacement for the TIP120.
