19 November 2012
CDAC Mohali
It happens all the time in the end of the marathon, you demand a "bonus time
like an elastic stretch". A stretch full of time limiting constraints. And then we
catch up new day’s sunlight, wear a charming and vibrant grace of being a
human and move on for the next. I guess life is like this, keep on moving,
growing, thinking. Here is another experience of mine about learning. I can say learning by fun. It was an intuitive turn in learning process of my M.Tech
curricula which generated a sense of interest about the field of Embedded Systems. I and some of my pals were adored with the electrifying teachings by
an expert. An expert with simple living and high thinking.
Time flies for those who are having fun. And these past four weeks have been
certainly that. The best and addictive phase of my life in front of the computer
screen.
Well, the concept which provoked me to write this article is directly
harmonious in learning Printed Circuit Board - Computer Aided Designing
techniques which are advertent towards the navigation and supervision of Shri.
Shavinder Singla sir, Deputy Engineer, CDAC, Mohali.
After a long suspension of documentation adjournments, we 2nd year metal
alloys (friends) from Embedded Systems and Engineering Production Design
Technology branch got the final recommendation to learn PCB-CAD using
Cadence OrCAD tool on 16.X.12 (first day of the class).
As most of you know that, PCB is a thin plate on which chips and other
electronic components are placed. For any electronics product, printed circuit
board (PCB) forms the basic foundation for interconnecting and packaging.
PCBs are used to mechanically support and electrically connect electronic
components using conductive pathways, tracks or signal traces etched from
copper sheets laminated on a non-conductive substrate.
Using “Capture CIS” tools we have to prepare an organized schematic of the
well designed circuit in application utilizing libraries and parts, giving the
footprint name to each component we used. Here, footprint is the
representation of the physical area that a component occupies on a PCB.
Further, “Layout Plus” tool in the OrCad software is the transference phase, it
means transferring the design from Capture to Layout. As Singla sir told us
"PCB’s consist of a number of electrical and non-electrical layers. 2 to 4
electrical layers are fairly common for simple circuit boards. 8 to 20 layers can
often be seen in many industry applications".
In our lab, we have the facility to fabricate two layered boards i.e. double sided PCB’s. Here in the starting of Layout, we have to place parts or components followed by the design rule check. Now after completion we have to route our design by manual routing. As per guidance, sir always mentioned – "One should think of the board as a work of art, so it can look consistent, readable, and fine. A clean design will ensure fabrication success". So, design cleaning is must by checking route spacing, not using right angles in tracks, pad exits should not come out at unusual angles, removing extra via holes as via add costs to the board and an orderly silkscreen should be uniformly used as a text tool to define component placing and details. Similarly sir also explained that documentation and packaging of the design is also helpful in manufacturing and debug. Now, one more concept is the Gerber Data Format which was elaborated on 16.XI.12 (last day of the class), it is used to define the images of copper layers, solder mask, drill holes. Gerber files are sent to PCB fabrication and loaded in Computer Numeric Control machines to prepare data for each step of the PCB manufacturing and production. It is obvious these things will appear at ease when one performs such creative de-facto works practically and analytically.
What specifically, I learned under the enthusiastic direction of Singla sir is the key responsibilities of PCB designer, which are: Schematic entry, Footprint creation, Proper component placement, Track-width selection, Routing, Creating NC/Gerber data, Ensuring DRC, design for manufacturability (DFM) - Design for assembly (DFA), Knowing IPC/Mil standards, Knowing electromagnetics, electromagnetic compatibility (EMI), electromagnetic interference fundamentals (EMC).
Every concept learned in the laboratory has an instrumental attachment with a tranquilizing track of songs occasionally played by Singla sir. A beautiful lab environment in a disciplined manner and joyous spirit. I think this is a major duty of seniors to motivate their juniors by spreading true knowledge and faithful learning in the fields where at first most of the paths and tracks seems to be zigzag, little stretchy, bit enigmatic demands perseverance resulting in the backing up of the morals and biasing of interests but then things get bright when you take initiative and get a genuine down to earth grip from experts and teachers with a pat on shoulder saying "we are behind, just take a step forward, and explore your strengths." I wish my juniors at CDAC, Mohali to challenge their limits and come out of their comfort zone to explore more out of this life.
Well, here is a short story which I always like and this is what our expert engineers always try to transmit in us: There was an engineer who had an exceptional gift for fixing all things mechanical. After serving his company loyally for more than 30 years, he happily retired. Several years later, the company contacted him regarding a seemingly impossible problem they were having with one of their multi-million-dollar machines. They had tried everything and everyone else to get the machine to work but to no avail. In desperation, they called on the retired engineer who had solved so many of their problems in the past. The engineer reluctantly took the challenge. He spent a day studying the huge machine. At the end of the day, he marked a small "x" in chalk on a particular component of the machine and stated, "This is where your problem is." The part was replaced and the machine worked perfectly again. The company received a bill of $50,000 from the engineer for his service. They demanded an itemized accounting of his charges. The engineer responded: "One chalk mark: $1; knowing where to put it: $49,999." It was paid in full and the engineer retired again in peace.
In our lab, we have the facility to fabricate two layered boards i.e. double sided PCB’s. Here in the starting of Layout, we have to place parts or components followed by the design rule check. Now after completion we have to route our design by manual routing. As per guidance, sir always mentioned – "One should think of the board as a work of art, so it can look consistent, readable, and fine. A clean design will ensure fabrication success". So, design cleaning is must by checking route spacing, not using right angles in tracks, pad exits should not come out at unusual angles, removing extra via holes as via add costs to the board and an orderly silkscreen should be uniformly used as a text tool to define component placing and details. Similarly sir also explained that documentation and packaging of the design is also helpful in manufacturing and debug. Now, one more concept is the Gerber Data Format which was elaborated on 16.XI.12 (last day of the class), it is used to define the images of copper layers, solder mask, drill holes. Gerber files are sent to PCB fabrication and loaded in Computer Numeric Control machines to prepare data for each step of the PCB manufacturing and production. It is obvious these things will appear at ease when one performs such creative de-facto works practically and analytically.
What specifically, I learned under the enthusiastic direction of Singla sir is the key responsibilities of PCB designer, which are: Schematic entry, Footprint creation, Proper component placement, Track-width selection, Routing, Creating NC/Gerber data, Ensuring DRC, design for manufacturability (DFM) - Design for assembly (DFA), Knowing IPC/Mil standards, Knowing electromagnetics, electromagnetic compatibility (EMI), electromagnetic interference fundamentals (EMC).
Every concept learned in the laboratory has an instrumental attachment with a tranquilizing track of songs occasionally played by Singla sir. A beautiful lab environment in a disciplined manner and joyous spirit. I think this is a major duty of seniors to motivate their juniors by spreading true knowledge and faithful learning in the fields where at first most of the paths and tracks seems to be zigzag, little stretchy, bit enigmatic demands perseverance resulting in the backing up of the morals and biasing of interests but then things get bright when you take initiative and get a genuine down to earth grip from experts and teachers with a pat on shoulder saying "we are behind, just take a step forward, and explore your strengths." I wish my juniors at CDAC, Mohali to challenge their limits and come out of their comfort zone to explore more out of this life.
Well, here is a short story which I always like and this is what our expert engineers always try to transmit in us: There was an engineer who had an exceptional gift for fixing all things mechanical. After serving his company loyally for more than 30 years, he happily retired. Several years later, the company contacted him regarding a seemingly impossible problem they were having with one of their multi-million-dollar machines. They had tried everything and everyone else to get the machine to work but to no avail. In desperation, they called on the retired engineer who had solved so many of their problems in the past. The engineer reluctantly took the challenge. He spent a day studying the huge machine. At the end of the day, he marked a small "x" in chalk on a particular component of the machine and stated, "This is where your problem is." The part was replaced and the machine worked perfectly again. The company received a bill of $50,000 from the engineer for his service. They demanded an itemized accounting of his charges. The engineer responded: "One chalk mark: $1; knowing where to put it: $49,999." It was paid in full and the engineer retired again in peace.
Thus, realizing the "stretch of bonus time" which we got as an extension in the
marathon as an athlete in the 4th week of PCB designing (learning Gerber
Data), I thought to invest this additional bonus employing few words on the
basis of my experience what I have learnt with the excellent faculty and
sharing it with you all.
So, guys take out your hat from your cart, bring it on, buy some cans of diet
coke, relish the taste of using the CAD tools, latch up your veins with
computer cables. Grow some beard and deploy yourself in fun learning mode.
"HEARTIEST THANKS TO SHRI SHAVINDER SINGLA SIR"
