6. CONSTRUCTION PCB WizardPCB Wizard is a strong application that can be used for designing circuit boards whether they are single sided or double sided printed. PCB Wizard is loaded with all the necessary tools that are needed at each step of PCB circuit designing. A large library of components has also been provided for the ease of use in PCB designing. These components can be easily inserted into your project and there is no need to draw them from scratch.PCB Manufacturing ProcessThe PCB manufacturing process is very important for anyone involved in the electronics industry.
Printed circuit boards, PCBs, are very widely used as the basis for electronic circuits. Printed circuit boards are used to provide the mechanical basis on which the circuit can be built. Accordingly virtually all circuits use printed circuit boards and they are designed and used in quantities of millions.PCB LayoutLay out of the desired circuit is the most important in any circuit board manufacturing process.
The following points are to be observed while performing the layout of the PCB. Sufficient space should be maintained between two components. High heat dissipation components like high voltage resistors should be mounted at a sufficient distance from the semiconductors and electrolytic capacitors. Components layout should make proper combination with copper side circuit layout. Circuit copper line thickness should be decided taking into account the current drain in the circuit. Etching processEtching process requires the use of chemicals acid resistant dishes and running water supply Ferric chloride is maximum used solution but other enchants such as ammonium per sulfate can be used. Nitric acid can be used but in general it is not used due to poisonous fumes. The pattern prepared is glued to the copper surface of the board using a latex type of adhesive that can be cubed after use. The pattern is laid firmly on the copper use a very sharp knife to cut round the pattern carefully a remove the paper corresponding to the required copper pattern areas. Then apply the resist solutions, which can be kind of ink proportion fort the purpose maintaining smoothing clean outlines as far as possible. While the board is drying test all the components. Before going to next stage, check the whole gotten and cross cheek against the circuit diagram check for any freeing matte on the copper. The etching bath should be in a galls or enamels disc. If using crystal of ferric-chloride these should be thoroughly dissolved in water to the proportional suggested. There should be 0.5 Lt. of water for 125 Gm. of crystal.Water liquid should be thoroughly deflated and druid in water land; never pour down the drain. To prevent particles of copper hindering further etching, agitate the solutions carefully be gently twisting or rocking the tray. The board should not be left in the bath a moment longer than is needed to remove just the right amount of copper. In spite of there being a resist coating there is no protection against etching away through exposed copper edges; this leads to over etching. Have running water ready so that etched. Drilling ProcessDrilling is one of those operations that call for great care because most of the holes will be made a very small drill. For most purposes a 1 mm drill is used Drill all holes with this size first those that need to be larger can be easily drilled again with the appropriate lager size. Component MountingAll components are mounted at their respective position as per the components layout. Proper precautions should be taken during mounting process. Component AssemblesFrom the greatest variety of electronic components available today, which runs into tens of thousands of different types it is often a perplexing task to know which the right task for a given job is. There should be damage such as hair line crack intuit opera on PCB that could age a serious office on the operational ability to the completed assemble. If there are than they can and should be repaired fiesta bye soldering a short link of bare copper wire over the affected part.The most popular method of holding all the items is to been the wires future apart after they even been indebted in the appropriate holes. This will hold the component in position ready for soldering. Some components will be considerably larger than other occupying and possible partially obscuring neighboring components. Because of this best to start by mounting the smallest first and progressing through to the largest. Before starting make certain that no further drilling I likely to be necessary because access may be impossible later. Next will probably be the resistor small signal diodes of other similar size components some capacitor are very small but it would be best to fit these after words when fitting each group of components marks of each one on the components it’s as it is fitted and if we have to leave the job we know where to recommence. Although transistor & integrated circuit are small items there are good reasons for leaving the soldering of these until the last step the main pint is that these components are sensitive to heart and is subjected to prolonged application to the soldering iron they could be internally damaged. All the components before mounting are rubbed with sandpaper so that oxide layer is removed from their tips. Now they are mounted according to the components layout.7. SOFTWARE USEDSCH Simulation Software Version 7.0.2This software is a easy-to-use schematic design program. Express SCH schematic design software is just as easy-to-use as our PCB layout software, both having the same user interface. After spending a few minutes to teach one, mastering the other takes no time at all Step 1: Select the Components Begin your schematic by placing the component Select the parts from the Component Manager Dialog box. Express SCH includes a large library with hundreds of component symbols (ICs, resistors, capacitors…) that you can use to draw your electronic circuits.Step 2: Positions the Components drag each component to the desired location on the page. The Snap to grid feature makes it easy to neatly align the symbols. If all of the components do not fit on a single page, add additional sheets. All the sheets of a schematic are linked together and saved in one.Step 3: Add the Wires Now draw the wires to connect the parts together. Add each wire by clicking on a component’s pin, then dragging the wire to the pin it connects to Step 4: Edit the Schematic making changes to a schematic is simple using standard commands such as Copy, Cut and Paste. Rearranging the components is easy by dragging them with the mouse. Wires always stay connected to their pins, even when you move things around Step 5: Link the Schematic and PCB after you complete your schematic, it can be linked to your circuit board layout file. This image of the Express PCB layout software shows how it guides you in designing your board by highlighting in blue the pins that should be wired together.ISIS Proteus Version 2.6Proteus is a simulation and design software tool developed by Lab center Electronics for Electrical and Electronic circuit design. It also possess 2D CAD drawing feature. It deserves to bear the taglineFrom concept to completion.It is a software suite containing schematic, simulation as well as PCB designing. ISIS is the software used to draw schematics and simulate the circuits in real time. The simulation allows human access during run time, thus providing real time simulation. ARES is used for PCB designing. It has the feature of viewing output in 3D view of the designed PCB along with components. The designer can also develop 2D drawings for the product.FeaturesISIS has wide range of components in its library. It has sources, signal generators, measurement and analysis tools like oscilloscope, voltmeter, ammeter etc.., probes for real time monitoring of the parameters of the circuit, switches, displays, loads like motors and lamps, discrete components like resistors, capacitors, inductors, transformers, digital and analog Integrated circuits, semi-conductor switches, relays, microcontrollers, processors, sensors etc.ARES offers PCB designing up to 14 inner layers, with surface mount and through Whole packages. It is embedded with the foot prints of different category of components like ICs, transistors, headers, connectors and other discrete components. It offers Auto routing and manual routing options to the PCB Designer. The schematic drawn in the ISIS can be directly transferred ARES.