Printed Circuit Board

Important Points

• Provides mechanical support

• Electrically connects electronic components using conductive pathways

• Also referred as PWB-Printed wiring Board

• PCB populated with components is called PCA or PCBA-Printed Circuit Board Assembly

      Materials

• Conductive path - copper foil

• Insulated layer - epoxy resin prepreg

• Dielectric - Teflon, FR4, FR5, FR6, CEM1, CEM3, CEM4, CEM5, G10 etc. 

                              ( FR4 is the most common )   

                               

      Trace

                     :- The conductive Cu path is called TRACE.

      Etching
                     :- Removing undesired Cu leaving only desired Cu traces is called 
                        Etching process.

     

      Production

• Silk screen printing       

• Photoengraving

• PCB Milling   

• Addictive process  

      Drilling

                    Drill bit - made of solid tungsten carbide.

                    Holes are filled with angular rings.

                        

       PTH - Plated Through Hole    

        Via :-        The electrically conductive plated holes in the PCB is called via.

        Types of via

• Standard via

• Bind via :- from one side of the board to one or two of the inner layer,                                         but it do not protrude through the other side                              

• Buried via :- connects one or more inner layers

    Multilayer  

• Silkscreen layer :- component overlay/ component layer ( top/ bottom )
• A multilayer PCB is made up of individual boards separated by pre-impregnated bonding of layers, also known as "prepreg" 

       Electrical testing :-

•  Flying probe test machine 
•  Bed of nails test machine 

       Board thickness :-  
       
       1.6 mm standard ( 0.8, 2.4 mm are also available )

       Surface finish :- 

       SMOBC-Solder Mask Over Bare Copper, HAL-Hot Air Leveling, Goldflash

       Notes :-

• 100 thou - 2.54 mm; 100 thou basic measuring point

• via:-  0.5 - 0.7 mm 

• R, C, D round pad and IC oval pad  

• High frequency traces are short

• Minimum 8 mm gap between 230 and isolated signal traces 

• Pad size should be at least 1.8 times the size of hole

 
                


 

10 best motivating thoughts

• Go back a little to leap further

• Every noble work is at first impossible

 

• The greatest mistake you can make; continuously be afraid you will make one

• Don't follow where the path may lead. Go instead where there is no path and lead a trail

• Life is tragedy for who feel and a comedy for who think

• Tomorrow never comes

• Commitment leads to action; action brings your dream

• Our destiny changes with our thoughts  

• To reach a port you must sail; not tie at anchor 

• Destiny is not a matter of chance; but a matter of choice. It is not a thing to wait; but a thing to achieve

Best 1000cc Superbike

        Which is the best 1000cc superbike?.Who doesn't know it is the YAMAHA YZF R1?, it doesn't matter the year whether it is 2010 or 2011, the race replica R1 is the king of performance.The R1 was born in 1998 with a breathtaking design and unbeatable performance. She had the most involving ride and razer sharp handling ever since 98. R1 revealed the definition of performance to the biking world. Her beautiful body made sleepless nights for every man in this entire universe. And she was a nightmare for other bike manufactures in this or any other universe. At that time every HONDA lover used to visit church twice a day for praying "Oh my GOD please help HONDA from getting defeated by the great YAMAHA R1". They also afraid they may change their mind to support HONDA.
                    
                   Yamaha made a benchmark by launching the R1 that is simply unbeatable by any other. They (HONDA,SUZUKI,KAWASAKI,and some other) tried  hard but the R1 simply remains unbeatable till 2011 and I hope it will remain forever. When YAMAHA launched R1 it was only the HONDA fans went to church but now it is the entire HONDA people include motogp riders goes not twice but more...

The YAMAHA had always produced great machines with mind blowing handling characteristics, the R1 is the BIG DADDY of them. Yamaha provides highly spirited, self sacrificing 182 Japanese horses that will definitely give enough speed and acceleration which may frighten even a man with iron hearts.

                   Every manufactures provides horses but it is only YAMAHA provides the most wild horses of all time.YAMAHA once again bags a high score by the launch of 2011 R1 that will make every other desperate run for an upgrade to cope with the hot R1 unaware that it is simply a herculean task

Features :
                    Power                             -    182 Japanese horses    
                    Capacity                          -    998cc 4 Cylinder
                   *The name R1 is enough
 

Yamaha YS250 to INDIA -

                        


               It is the new kid from YAMAHA stable to India.Its another dream come true for every Yamaha lover.The long waiting for a 250 cc full fledged naked bike is coming to an end.This hot naked is now on sale in Brazil and Europe and Yamaha has plans to bring it to India very soon.

         The 250cc market is getting hotter and hotter everyday. As a global player Yamaha cannot simply remain just a witness so they are going to make some groundbreaking moves soon.

         

Now the present 250cc market is ruled by world renowned Kawasaki Ninja 250 and few days before the Japanese giant Honda has entered into this segment with its CBR250. The KING OF PERFORMANCE is also planning to launch a 250cc naked bike.

Features:

(expected)

• Capacity :                    250 cc Air cooled, four stroke, single cylinder,SOHC
• Power    :                     25bhp (Expected)
• Bore x Stroke               74 x 58 mm
• Dry-Weight                  153 kg 
  
  
   
   
  
  
  

Endosulfan - enemy of human race

It will be a terrible mistake if we didn't speak against this pesticide. We have seen a lot of victims of Endosulfan in our life, we know Endosulfan will harm many but we are keeping silence...why ?.The question makes pain in my heart that I can't suffer any more. We are human beings...we say so. If we do, we should open our eyes towards this calamity and act as we can to STOP this situation...happened...no..created by Endosulfan.
                          
                         What is the need of a thing that makes our life worse...do we need that?..the answer is NO. We know agriculture is started even before the inventions of these modern pesticides.Farmers get good results even better than today on that day when these harmful pesticides are being not used. That proves we can do farming without the use of harmful pesticides.

                        If we are ready to analyze problems occurs nowadays in human life...we can find that all these problems are evolved when people are going away from nature...when people are going toward making wealth through anyway.

 Don't we need a solution to end this calamity...Yes we need...We could say we need solution if have a heart..I think you have one and agree with me...If you do... say as loud as you can  BAN ENDOSULFAN

                                                        

Responsibilty of youth

It is high time to join the hands of the youth against corruption in India for a bright and shining India. The change is essential and it can only bring by the youth of India including you. The responsibility lye not only in the hands of political parties or government officers, we all Indians are responsible for this present situation.

If we are ready to think that there is no other way in building a prosperous India other than hard work from every Indian with a burning desire. We should not make any delay in working for our motherland.

Everywhere man blames fate, yet his fate is mostly but the echo of his character and passions, his mistakes and weaknesses. So we should not repeat any more mistake. We must show the courage to think wisely and work hard for our motherland