The Engineering Projects

Introduction to 1n5819

Hi Guys! We always feel happy when you come over to browse useful information that meets with your needs and requirements. Electronic components used in electronic industry are the backbone of recent technology that make our lives easy and help us get rid of the most conventional ways of running electronic projects. Today,  I am going to discuss the details on the Introduction to 1n5819. This is a metal to silicon power diode, also termed as Schottky Rectifier, that applies Schottky Barrier Principle. It is mainly used as rectifiers in high frequency low voltage inverters, polarity protection diodes and free wheeling diodes. I'll try to cover each and everything related to this transistor so you don't need to go anywhere and find all information in one place. Let's dive in and unlock the properties of this diode.

Introduction to 1n5819

• 1n5819 is a metal to silicon power diode that applies Schottky Barrier Principle. It is also referred as Schottky Rectifier(named after Scientist Walter H. Schottky), surface barrier diode, hot electron diode or hot carrier diode.
• This diode is mainly used as a rectifier in many devices including high frequency low voltage inverters, polarity protection diodes, free wheeling diodes and radio frequency applications.
• It is little bit different than normal PN junction diode where metal like platinum or aluminium are used in place of P-Type semiconductor.
• In Schottky diode, semiconductor and metal joined together, forming a metal-semiconductor junction where semiconductor side acts as an cathode and metal side acts as a anode.
• When metal-semiconductor junction formed between metal and semiconductor, they result in depletion layer also referred as Schottky barrier.
• Schottky comes with low stored charge and exhibits low power loss and high efficiency mechanical characteristics.

• It is manufactured in such a way that all external surfaces are corrosion resistant and terminals are easily solderable where current flows in one direction only and it stops the current flowing in other direction.
• Maximum temperature it can withstand for soldering purpose is 260 °C.
• Guard ring die construction gives it transient protection and high surge capability.
• The power drop occurred in this diode is lower than PN junction diodes.
• The Schottky diode is a semiconductor diode that comes with fast switching applications and it pertains to less unwanted noise as compared to PN junction diode which makes it an ideal choice for most of the switching applications.
• When voltage is applied across the diode terminals, current starts to flow which results is small voltage drop across the terminals.
• The voltage drop in this diode lies around 0.15 to 0.45 which is very low as compared to regular diode where voltage drop lies between around 0.6 to 1.7 V.
• The lower voltage drop results in higher efficiency and higher switching speed.
• The voltage drop is actually referred as a voltage required to turn on the diode.
• The voltage required to turn on the germanium is same as Schottky diode, but germanium diodes are not used in most of the applications because they feature very less switching speed as compared to germanium diode.

How Schottky Diode 1n5819 Works

• Working of Schottky diode is slightly different than normal PN junction diode where P-Type semiconductor is replaced by metal.
• When metal and semiconductor are joined together, they shape a metal-semiconductor junction which allows the flow of electron from higher energy level to lower energy level.
• As the electrons available in N-Type semiconductor exhibit more energy and start flowing from semiconductor to the metal region.
• We know when atom loses an electron, it results in positive ion and when atom gains electrons it results in negative ion.
• Similarly, when N-Type semiconductor loses electron, it clothes positive charge on it and the electrons that go to the metal allow it to cloth negative charge on it.

• The positive and negative charges appearing on the metal and semiconductor region are nothing but the depletion region.
• The electronic width available in the n-type semiconductor is much larger than the electronic width that allows the electron to move from semiconductor to the metal.
• Basically built-in-voltage houses inside the semiconductor that can be seen by the conduction bands when electrons try to move to the metal region.
• In order to move electrons from semiconductor to the metal region, the positional energy of the electrons must be greater than the built-in-voltage.
• We are referring unbiased Schottky diode where only small number of electrons pass from semiconductor to metal region because built-in-voltage creates a barrier which refrains the large movement of electrons from semiconductor to the metal region.

Absolute Maximum Ratings of 1n5819

Following figure shows the absolute maximum ratings of 1n5819.

• It is important to note that these are the stress ratings, which if exceed from absolute maximum ratings, can damage the device severely.
• Similarly, if stresses are applied for extended period of time, they can effect the reliability of the device.

Comparison between Schottky Diode and PN junction Diode

• There are number of differences between Schottky diode and PN junction diode. The Schottky diode is a uni-polar device because conduction is carried out by the movement of electrons only. Conduction through holes is very negligible as compared to conduction through electrons.
• PN junction diode is a bipolar device where conduction is carried by the movement of both charge carriers i.e. electrons and holes.
• In Schottky diode, the reverse breakdown voltage and depletion region is very small or negligible as compared to silicon PN junction diode.
• Similarly, the voltage drop across Schottky is very low as compared to PN junction diode which makes it suitable for many switching applications.

Applications

Schottky diodes come with a number of applications including

• General purpose rectifier
• Radio frequency applications
• Detect signals and power supplies
• Logic Circuits
• Polarity protection diodes
• Free wheeling diodes

That's all for today. I hope you have enjoyed the article. We love to keep you updated with relevant information that helps you resolve your questions and queries. However, if you feel skeptical or have any question you can approach in the comment section below.I'll get back to you as soon as possible and help you with best of my expertise. Thanks for reading the article. Stay Tuned!

Introduction to TIP120

Hi Friends! We welcome you on board. Electronic industry is already filled with a number of devices and components that help ease the daily life of a common man. However, there is always much room for innovation in the electronics industry when it comes to facilitating the customers. When there comes a requirement for switching and amplification, there is a need for transistors. Today, I am going to unlock the details on the Introduction to TIP120. This is an NPN Darlington transistor which is mainly used for general purpose amplification and medium power switching applications. It 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 much higher current gain as compared to if each transistor is taken separately. Before we move on, you must have a look at BJT (Bipolar Junction Transistor) that I have updated recently. Let's get started.

Introduction to TIP120

• TIP120 is an NPN Darlington transistor which is mainly used for general purpose amplification and medium power switching applications.
• It mainly consists of an emitter, base, and collector which are the basic parts of any transistor. This is a bipolar power transistor where conduction is carried out by both charge carriers i.e. electrons and holes but main charge carriers are electrons as this an NPN transistor.
• 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 much higher current gain as compared to if each transistor is taken separately.
• In this NPN Darlington configuration, the emitter of the first transistor is connected to the base of the second transistor which allows the current amplify.

• Transistors are electronic switches that fulfill the power requirement of the project. When normal transistors are not enough to meet the power requirement of the projects, we replace normal transistors with Darlington transistor that are same as regular transistors with some exceptions i.e they are capable of driving a much larger load.
• When a voltage is applied at the base side, it gets biased and draws small current which is used to control large current at the collector and emitter side.
• This transistor comes with a DC current gain of 1000 and can switch up to 60 V with a peak current of 8A.
• This device is developed using planar technology and incorporated into a monolithic Darlington configuration. It exhibits exceptional high gain performance and low saturation voltage.
• It comes with a much higher current gain which means a small amount of current from a microcontroller or sensor can be used to drive a much large load.
• This is an NPN transistor that comes with electrons as major charge carriers. While PNP transistor comes with holes as major charge carriers.

TIP120 Pinout

This transistor mainly comes with three terminals as follow 1. Base 2. Collector 3. Emitter

• Movement of electrons plays an important role in defining the nature of conductivity of the transistor. In this transistor main charge carriers are electrons.
• As it is an NPN transistor so the base is positive with respect to the emitter. And collector voltage is much larger than base voltage.

Circuit Diagram of TIP120 to Control Motor

Following figure shows the circuit diagram of TIP120 to control motor

• This is the circuit to control 5 V motor which draws 1 A of current.
• TIP120 doesn't appear to be very efficient while controlling 5 V motor because it is not a regular transistor but a pair of transistors which are connected together to shape a single product which allows driving a larger load.
• However, achieving high gain comes with some drawback and limitations as results in a higher voltage drop.
• Higher current designs cause more heat that can melt the components involving in the project. In order to remain in a safer side, you can add a heatsink, that helps in the heat dissipation and prevents the circuits from catching fire.
• This transistor is a current controlled device which is different than MOSFET that is voltage controlled device.

Absolute Maximum Ratings

Following figure shows the absolute maximum ratings of TIP120 Darlington transistor.

• These are the stress ratings. In view of these stress ratings, you must keep few things into consideration.
• These stress ratings must not exceed the absolute maximum ratings otherwise they can damage the device.
• Similarly, if these stresses are applied for a maximum period of time, they can affect the device reliability.

Applications

• This transistor is mainly used for general purpose amplification.
• Medium power switching applications make use of this transistor because it exhibits more power than a regular transistor.
• Darlington transistors are used in high current circuits, especially in computer control of motor applications where current is being amplified from the computer to the level required for the connected device.

That's all for today. I hope you have enjoyed the article. However, if you feel skeptical or have any question you can approach me in the comment section below. I'd love to help you according to best of my expertise. Keep us updated with your feedback and suggestions, they allow us to give you quality work that resonates with your needs and expectations and helps you keep coming back for what we have to offer. Thanks for reading the article. Stay Blessed!

High Frequency PCB

Hi Guys! I hope you are enjoying life and getting most out of it. In terms of ease of use and availability, some components and devices become the integral part of electronics, PCB is one of them. PCB not only removes the need of end to end wiring, but it also covers less space and weight and turns out to be less costly. Today, I am going to add High Frequency PCB in our descriptive list of articles related to PCB and its types. High Frequency PCB is a type of PCB which is widely used in applications involving special signal transmission between objects. It is available in frequency range of 500MHz to 2GHz and is an ideal choice for mobile, microwave, radio frequency and high speed design applications. If you are interested in embedded system, then you can use Proteus Ares to design your PCB. I'll try to cover whole topic related to High Frequency PCB from every aspect so you can grab the main concept very easily. Let's dive in and explore what is High Frequency PCB and how it has affected electronic industry?

High Frequency PCB

• We are familiar with the word PCB, some of you who are not, it is an acronym of Printed Circuit Board which uses conductive tracks and paths to electronically connect different components on the board.
• Copper is used to provide conductive path on the board which is laminated on the substrate material which is mostly made up of epoxy resin.
• Signal communication plays a vital role in electronic projects specially when it comes to WiFi and satellite system.
• Where there is a need of signal communication between two objects, there is a need of high frequency boards.
• High Frequency PCB is a type of PCB used for signal transmission  in the variety of applications including mobile, microwave, radio frequency and high speed design applications.
• High Frequency boards come with high frequency laminates are difficult to fabricate because they need to maintain thermal heat transfer of the application, in view of the sensitivity of the signal.
• Special materials are used to attain the high frequency given by the High Frequency PCB.
• Characteristics of the high frequency board can effect the overall performance of the signal, similarly any change in the Er value of the materials used can widely impact the impedance of the board.
• Most of the professionals prefer rogers dielectric material because it turns out to be less expensive, have low DK and DF value, reduced signal loss and appears to be suitable for fabrication and prototyping applications.
• Teflon is another common material used in the manufacturing process of the high frequency PCB, which comes with frequency of 5GHz.
• Some people are concerned about if FR4 can be used for RF applications? FR4 can be used in many applications requiring 1GHz to 10GHz frequency. But these FR4 based products come with their own drawbacks and limitations, they fail badly when high frequency is required for the signal transmission.

• In terms of DK, DF and water absorption factor, Teflon is the best, but more expensive than FR4.
• If your projects requires frequency more than 10GHz with higher quality and stable signal, then Teflon is the best choice.
• High frequency signals are vulnerable to noise and come with much tighter impedance tolerance as compared to conventional circuit boards.
• However, proper bend radius and accurate ground plans on impedance traces can help you design a product that can work in an effective way.
• By considering the certain parameters like coefficient of thermal expansion, dielectric constant, dissipation factor, temperature coefficient, thermal coefficient and quality of the material used can help the manufacturer design a final product that resonates with the client's needs and expectations.
• Ground plane is an important part in high speed design applications, because it not only retains the quality of the signal but also helps in reducing EMI emissions. It works nicely by providing controlled impedance traces that resonate with load and electrical source. It plays an important role in keep the signal connected with their return path.
• If you are interested to make PCB design by yourself, you can choose any of these top 10 PCB designing software. 

Prior Considerations

• The development of layout design is the most crucial part in making high speed products.
• If you are not expert in designing a layout design, you must have few words with the person who is going to make your layout design.
• Simple measures taken in the early stage can save you bunch of time in the later stage in case any remaking of the layout design is required.
• Give proper instructions and guidance to the layout designer so he can incorporate your idea in real time.
• Your instructions must include the sketch of the board, number of layers and signal layers on the board, thickness of the board, location of critical components on the board, location of bypassing components and the nature of critical traces, and the distance between the traces and the components, infact each and every thing you must keep in handy before you look for layout designer.

How to Pick a PCB Material

• Before you pick High Frequency PCB and suitable material for your project, you must take few things into considerations:
• Dielectric constant is the ability of material to store energy in the electric field. It is dependent on the direction of the material i.e. it will change as the axis of the material changes. It must be small enough so it delivers stable input in order to avoid any delay in the transmission signal.
• Similarly, Dissipation Factor must be small, because high DF can severely effect the quality of the transmission signal. So less DF will pertain to less signal wastage.
• Loss Tangent is another factor based on the moleculer structure of the material that can effect the RF material containing high frequencies. However, it is not of much concern for the low frequency signals.
• Proper spacing is very important in terms of cross talk and skineffect. Crosstalk happens when board starts interacting with itself and pertains to undesired coupling with their own components. In order to avoid crosstalk, distance between trace and plane must be minimum.
• Skineffect is directly connected with the resistance of the traces. It starts increasing when resistance increases which ultimately results in warming the board.So trace width and length must be selected in a way that it can not effect the board at higher frequencies.

• Smaller diameter vias come with low conductance and are most suitable as frequency go higher.
• Higher the value of Peel off resistance, impact endurance, and heat resistance, the better the quality of the signal.
• Coefficient of thermal expansion defines the effect of temperature on the size of the material. It widely effects on the drilling and assembly process of the PCB, because slight change in temperature can severely alter the size of the material. The thermal expansion of the copper foil must be same, because difference in thermal expansion may result in the separation of copper foil, in case material is subjected to changing temperature.
• Environment is a big concern in which your device is operating. If your device is going to be used in Lab or indoor environment then moisture won't be a big issue. Problem arises when your device exposes in wet environment. So, water absorption of the material should be low, because high absorption factor may alter the DF and DK value in the moisture.

Following are some materials that can be used for high frequency:

• Rogers 4350B HF
• Rogers RO3001
• Rogers RO3003
• Taconic RF-35 Ceramic
• Taconic TLX
• ISOLA IS620 E-fibre glass
• ARLON 85N

Once the design and material selection have been completed, designers strive to start a manufacturing process while keeping the key process variables in consideration such as maintaining the line width and dielectric spacing to ensure the robust design that resonates with the design requirements and delivers consistent performance in most effective and reliable way. You can also get benefit of online PCB design services, here are top online PCB design services. 

How to Create Controlled Impedance Transmission Lines

• Development of controlled impedance transmission lines is very important in order to avoid any signal loss.
• There are two common ways to make controlled impedance transmission lines named as Microstrip and Stripline methods.
• Microstrip is the existence of the trace on the top layer that comes with a ground plane below.
• Calculating the impedance of a mircostrip is little bit tricky and complex though and depends on various factors including relative permitivity of the board material, thickness and width of the trace and its height above the plane. In order to achieve better result, ground plane must be closer to the top layer.

• Stripline is another addition to control impedance which is quite identical to microstirp with one exception i.e.it comes with an extra group plane on the top of the trace.
• In this case, trace must be placed between the layers of two planes.
• Stripline is better as compared to microstrip because it has an ability to contain EMI radiation within the two planes.

Applications

• High Frequency Products can be observed in number of applications including advanced communications systems, and industrial and medical applications.
• Similarly cell phones, GPS receiver, RF remote control, ZigBee make use of high speed products for better signal transmission.
• High speed test equipments are comprised of high speed products that provide better performance throughout the life span of the application.
• Airborne and Ground based radar systems are a true example of high speed circuits.

The demand of high speed products is on the rise in electronic industry. They meet the requirements of the customers where regular circuit boards fail to deliver efficiently. However, you can choose any of these different types of PCBs based on your needs and requirements. If you feel skeptical or have any question you can approach me in the comment section below. We go extra mile to help resolve the queries of the visitors. Feel feel to keep us updated with your valuable feedback and suggestions, they allow us to give your quality work so you keep coming back for what we have to offer. Stay Tuned!