Introduction to 1n4738a

Hi Guys! Hope you are doing well. I am back to give you nuggets of valuable information related to engineering and technology so you can excel and grow in your relevant field. Today, I'll unlock the detailed Introduction to 1n4738a. It is a zener diode that comes with high power rating and is mainly used in stabilizing and clipping circuits. The zener diode is slightly different from regular diode as former can conduct in both directions while later conducts in one direction only. It is available in double slug construction with corrosion resistant surfaces, helping to operate it under high temperature and pressure. I'll try to cover each and everything related to this diode, so you don't have to grapple your mind surfing the whole internet and find all the information in one place. Let's jump right in and get down to the nitty-gritty of 1n4738a.

Introduction to 1n4738a

1n4738a is a zener diode that comes with an ability to conduct in both directions. It is a high power device mainly used in stabilizing and clipping circuits.
  • This zener diode features maximum lead temperature for soldering around 230 C. It comes with a zener voltage around 8.2 V and external leads are attached with the body, helping thru-hole mounting.
This zener diode is nothing but a p-n junction diode with current capability conducting in both directions i.e. forward direction and reverse direction, featuring very effective working characteristic with a power dissipation of around1300 mW.
  • You can not make it work in a reverse biased condition unless reverse breakdown voltage is achieved before the normal device operation.
It is important to note that the voltage drop across the zener diode doesn’t change over a wide range of voltages, which makes it a valuable pick for voltage regulation applications.
1n4738a Working
This zener diode is similar to a normal diode when it operates in a forward biased condition. However, working in a reverse biased condition is a totally different story that will only take place when the reverse voltage reaches the breakdown voltage, making diode flow current from cathode to anode.
  • When a wide range of applied voltage is applied, the corresponding current reaches to a maximum point and strive to stabilize itself after some time. This process will make the diode working as a voltage stabilizer.
The Voltage Breakdown state can be achieved in two ways: using Zener Breakdown Effect or Impact Ionization. These mechanisms start to happen at 5.5 V and don’t require different circuitry for a flawless working process.
  • However, the temperature coefficient sets them apart from each other as Zener effect comes with a negative temperature coefficient while the impact ionization features a positive temperature coefficient. And both effects cancel each other at 5.5 V, helping zener diode to gain the stable and reliable state over a wide range of temperatures.
1n4738a Absolute Maximum Ratings
Following figure shows the absolute maximum ratings of 1n4738a.
  • If stresses are exceeded above these absolute maximum ratings, they can damage the device.
  • Similarly, if stresses are applied for the extended period of time, they can affect the device reliability.

Applications

This zener diode is widely used in consumer electronics. Following are the major applications it can be used for.
 As a Waveform Clipper
Zener diode serves as a waveform clipper when connected in series. In this case, it will clip the waveform from both ends of the cycle i.e. positive end and a negative end of the cycle. In zener diode, the signal we get at the output comes with some major voltage spikes. However, if diodes are connected in series, they impede the diode from producing spikes, eventually modifying the output signal with a smooth waveform.
As a Voltage Shifter
  • Zener diode is widely used as a Voltage shifting device.
  • As a voltage shifter, it strives to make both output and breakdown voltage equal in magnitude.
That’s all for now. I hope I have given you everything you needed to known about 1n4738a. If you are unsure or have any question, you can approach me in the comment section below. I’d love to help you the best way I can. You are most welcome to feed us with your valuable suggestions, they help us provide you quality work. Thanks for reading the article.

Introduction to 2sa1265

Hi Guys! Hope you are doing well. Welcome you onboard. Today, I'll unlock the detailed Introduction to 2sa1265 which is a PNP transistor mainly used for power amplifier applications and proves to be an ideal choice for 70W high fidelity audio frequency amplifier output stage applications. This PNP transistor falls under the category of Bipolar Junction Transistors where two charge carriers i.e. electrons and holes take part in the conduction process, however, holes are major charge carriers in the PNP transistors, unlike NPN transistors where electrons are the major charge carriers.
  • BJTs are different than that unipolar transistors like JFETs as former is the current controlled device and later is a voltage controlled device. Both are used in different areas ranging from consumer electronics, industrial to commercial applications.
In this post, I'll try to cover some basic details related to 2sa1265, its main features, pinout, working, and applications. Let's jump right in.

Introduction to 2sa1265

2sa1265 is a PNP transistor mainly used for power amplifier applications. It is composed of three layers: two P doped layers and one N-doped layer which is sandwiched between the other two layers.
  • This transistor contains three terminals known as an emitter, base, and collector. The base terminal is more negative than the rest of the terminals.
These terminals come in different size and doping concentration. The emitter terminal is highly doped and features 100% of the transistor current while the base terminal is lightly doped and controls the conduction inside the transistor. The collector terminal is moderately doped and is bigger in size than other terminals.
  • The PNP transistor won't be conducting if there is no supply voltage at the base terminal, however, when a voltage is applied at the base terminal it draws current which is then used to control large current at other terminals.
It is important to note that, both NPN and PNP are used for amplification purpose but voltage polarities and current directions are reversed in both transistors i.e. in NPN transistor current flows from collector to emitter and in PNP transistor current flows from emitter to collector.
  • The 2sa1265 PNP transistor comes with two PN junctions i.e. emitter-base junction and the collector-base junction where former is forward biased and later is reverse biased.
Under normal conditions, the PNP transistor comes with voltage drop out of 0.7 V, so the voltage at the base side must be 0.7 V less than the voltage at the emitter side for making emitter-base junction a forward biased.
2sa1265 Pinout
Following figure shows the pinout diagram of 2sa1265.
  • In the case of PNP transistor, emitter voltage is much larger than collector voltage which is necessary for the transistor to conduct.
  • The transistor turns on as a small current starts flowing from emitter to base terminal.
2sa1265 Circuit Diagram and Working
Following figure shows the circuit diagram of 2sa1265. When a voltage is applied at the base terminal, the majority of holes move from the emitter and get diffused into the base terminal, combining with the electrons.
  • As the base is very thin and lightly doped it cannot hold the number of electrons for a maximum period of time, ultimately allowing the electrons flow from base to collector terminal.
In many amplification applications, NPN transistors are preferred over PNP transistors because conduction carried out by the movement of electrons is preferable over the conduction carried out by the movement of holes.
  • Combination of PNP transistor with NPN transistor is widely employed for the development of the power amplifier circuits. Power B amplifiers are a great example of this amplifier circuits where both PNP and NPN transistors are joined together to produce a high amplification cycle.
2sa1265 Absolute Maximum Ratings
Following figure shows the absolute maximum ratings of 2sa1265.
  • These are the stress ratings defined by the manufacturer. If you want the device to be running properly without any damage and undergoes a longer life, you must follow these operating conditions.
  • If these ratings are provided for the larger amount of time than the normal operating condition, they can affect the device reliability which may cause more damage in the later stage once your electronic project has been executed.
Applications
  • It is used in power amplifier applications.
  • An ideal choice for 70W high fidelity audio frequency amplifier output stage applications.
That's all for now. I hope I have given you everything you needed to know about 2sa1265. If you are unsure or have any question, you can ask me in the comment section below. I'd love to help you according to the best of my knowledge. Thanks for reading the article.
Syed Zain Nasir

I am Syed Zain Nasir, the founder of <a href=https://www.TheEngineeringProjects.com/>The Engineering Projects</a> (TEP). I am a programmer since 2009 before that I just search things, make small projects and now I am sharing my knowledge through this platform.I also work as a freelancer and did many projects related to programming and electrical circuitry. <a href=https://plus.google.com/+SyedZainNasir/>My Google Profile+</a>

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Syed Zain Nasir