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Introduction to 2n3055

Hey Guys! Hope you all are doing great and having fun with your lives. I am back to feed your stomach with plenty of information so you can progress and grow in real life. Today, I am going to unlock the details on the Introduction to 2n3055. It is a semiconductor NPN (negative-positive-negative) power transistor which comes in TO-3 Casing. I'll try to cover as many aspects possible related to this device so can get a brief overview about what it does and what are the applications it is used for. Let's get started.

Introduction to 2n3055

• The 2n3055 is a semiconductor NPN bipolar transistor which consists of three terminals called emitter, base, and collector.
• Unlike FETs(Field effect transistors) it is a current controlled device in which small current at the base side is used to control a large amount of current at the emitter and collector side.

• It is a bipolar device in which conduction is carried out by the movement of both charge carriers i.e electrons and holes.
• The measure of base current to control the large current at the emitter and collector side is used for amplification purpose.
• As 2n3055 is an NPN transistor, here base with positive with respect to emitter and P layer lies between the two layers of N doped semiconductor.
• P-doped layer of transistor acts like a base while other two N sides represent emitter and collector respectively.
• It comes with lots of electronic applications but mostly it is used for switching and amplification purpose.
• This NPN transistor can be configured with three configurations named as a common collector, common base, and common emitter configuration.

• It is important to note that it won't be useful for amplification purpose when it is configured with common emitter configuration as it encompasses a transition frequency of around 3 MHz that will allow the forward current gain drop to 1.
• The maximum collector-emitter voltage is highly dependent on the resistance intensity between emitter and base, provided by the external circuit.
• The 2n3055 is connected to a heat sink which widely effects the overall power dissipation by the transistor.
• However, in most of the application when an ambient temperature is high, low power dissipation is expected.
• This device is manufactured in such a way it can function with an efficient heat sink.
• However, proper care should be given in order to mount the device perfectly, otherwise, it can harm the device at large.
• Mica insulator is added in the manufacturing process that isolates the case of the transistor from the heat sink.
• This transistor is a bipolar current controlled device which is different than JFET which is a unipolar voltage controlled device.

2n3055 Pinout

2n3055 consists of three terminals which are given below. 1: Emitter 2: Base 3: Collector Pinout of 2n3055 is given in the figure below.  

• A small amount of base current is used to control the large current at the emitter and base side.
• Conduction is carried out when electrons emit from the emitter and are collected by the collector.

Circuit Diagram of 2n3055

The circuit symbol of 2n3055 is shown in the figure given below.

• As it is an NPN silicon transistor so it has positive base terminal and a negative emitter terminal.
• This transistor is a current controlled device where a small amount of current at the base side is used to handle a large amount of current at the emitter and collector side.
• The NPN and PNP transistor encompass same features with some exceptions i.e. Current will sink into the base side in case of PNP transistor while current from the base side will source to the transistor in case of NPN transistor.
• Emitter current is the sum of base and collector current.
• Transistor forward current gain can be found by dividing the collector current to the base current. It is also called beta current and is denoted by ß. Beta has no units as it is a ratio between two currents.
• Beta value is used for the amplification purpose. Beta value ranges between 20 to 1000, however, its standard value is 200.
• At positive base to collector voltage, the ratio between collector current to the emitter current is called current gain of the transistor and is denoted by alpha a.
• The value of alpha lies between 0.95 to 0.99, however, in most of the cases it is considered as 1.

Maximum Rating of 2n3055

Absolute maximum rating of 2n3055 are given below

• It dissipates power around 115 W when the case temperature is set to 25 degrees.
• It is a 60 V and 15 A device which comes with a base current of 7 A and forward current gain ranges between 20 to 70.

Applications

• It is widely used in lots of applications where amplification of the signal is required.
• It is used for switching purpose.

That's all for today. I hope you have got a clear idea about this NPN transistor. However, if you still feel any problem in understanding the concept of this NPN transistor, you can ask me in the comment section below. I'd love to help you in this regard. Thanks for reading the article. Stay Tuned!

Introduction to 2n7000

Hi Everyone! I hope you all are doing great. I am back to whet your appetite with daily dose of information and knowledge that puts you ahead from others and makes you stand out of the party. Today, I am going to give you the Introduction to 2n7000. It is an enhancement type N-Channel MOSFET which is mostly used for low power switching applications. It comes with different current ratings and lead arrangement. I am going to give you a brief detail about this component, so you don't have to go any where else to find information regarding this device. Let's get started.

Introduction to 2n7000

• 2n7000 is a uni-polar N-Channel Enhancement mode MOSFET which comes with terminals called drain source and gate.
• In this transistor, the input voltage applied at the gate terminal is used to control the conductivity between source and drain.
• The conducting path between source and drain is called channel whose length can be controlled by the input voltage at the gate terminal.

• As it is an enhancement mode MOSFET, it is assumed as OFF i.e. it doesn't conduct under normal operating condition when Vgs=0. It will start conducting when some input voltage is applied at the gate terminal.
• 2n7000 is a 60 V device and comes in TO-92 enclosure. Sometimes, it is termed as FETlinton and it an N-Channel MOSFET, so here conduction is carried out by the movement of electron rather than holes.
• It is a voltage controlled device which is widely used in place of other BJT(Bipolar junction transistors).
• However, it has many advantages over BJTs, as it requires no biasing for gate i.e. gate draws no current however, we need small surge current in order to charge the capacitance at gate terminal.
• It comes with high impedance and insulated gate, sometimes it is referred as IGFET(Insulated Gate Field Effect Transistor).

• As gate draws no current so it doesn't need any current limiting resister at the input of the gate terminal. However, protection gate resistor is required for the 2n7000 when it is used for the circuits that come with external gate vulnerability.

2n7000 Pinout

2n7000 is a uni-polar voltage controlled device which consists of three terminals. 1: Source 2: Gate 3: Drain  

• Gate is practically isolated from drain and source and it draws no current.
• There is an insulation layer that lies between the gate and the body of transistor.

Working of 2n7000

• In 2n7000, the conduction between source and drain is carried out by the movement of electrons.
• In this transistor, source and drain are made up of n-type material while its body and substrate is made up of p-type material.
• In 2n7000, gate is biased by applying the positive input voltage that will attract the electrons available in the p-type semiconductor substrate.
• The gate of this transistor is used composed of layer of poly-silicon.
• When we add Silicon dioxide on the layer of substrate it gives the typical metal oxide semiconductor construction.
• Silicon dioxide is a dielectric material so it will act as a capacitor where one of its electrodes will be replaced by the semiconductor.
• If we apply positive voltage at the MOS structure, it will alter the charge distribution in the semiconductor. With the addition of positive voltage, the holes present under the oxide layer will experience a force and allow the holes to move downward. The depletion region will be accumulated by the bound negative charges which are associated with acceptors atoms.
• The overdose of free electrons available in the p-type substrate increases the overall conductivity of channel, and constantly inverts the electrical properties of p-type substrate, allowing the substrate to change into n-type material.
• The positive voltage applied on the gate terminal control the movement of electrons. As we increase the positive change at the gate terminal the more it will attract the electron, hence resulting in widening the channel path between source and drain terminals. Thus, increasing the positive voltage at the gate terminal will increase the overall conductivity of the transistor.
• This N-Channel transistor is composed to reduce on state resistance and give efficient switching performance.

Maximum Rating 2n7000

Maximum rating of 2n7000 are given in the figure given below.

• Drain-Source voltage is 60 V while Drain current is 200 mA.
• Power dissipation is about 350 mW.
• If values are exceeded more than the given values, they can harm the device at large.

Difference between N-Channel MOSFET and BJT

• N-Channel MOSFET are unipolar devices and BJT are bipolar devices.
• BJT are current control devices while MOSFET are voltage controlled devices.
• In BJT, we need base current to control the large amount of current at emitter and collector. In MOSFET, no biasing is required at the gate side as it draws no current. However small initial current is needed to charge the capacitance of the transistor.

Applications

• 2n7000 is mostly used for low power switching applications.
• It is used as a driver for motors, relays and lamps.
• It is widely used in battery operated systems and solid state relays.
• High speed circuits use MOSFET 2n7000 as it requires no buffer.

That's all for today. I hope you have enjoyed the article. I always try my best to give you quality work that requires minimum effort from your side to digest this information completely. However, if still you need any kind of help, you can ask me in the comment section below, I'd love to help you in this regard. Thanks for reading the article. Stay Tuned!