Electronex 2014

It's Sydney's turn to host Electronex 2014,  September 10 -11 at Australian Technology Park.  

This must see show for the electronic engineers, product developers and manufacturer's features the latest technology and services on offer in Australia and overseas. Electronex is the most cost effective means of sourcing product and solutions in the one day.  With direct personal access to suppliers and industry experts you can compare and examine products and services and create new business opportunities.

Fine-Mark Design will be exhibiting on stand A19.  Find out how our PCB service can help you cut costs and boost productivity.   

Register here for Electronex 14

Engineers are being thrown into the deep end when it comes to designing PCB’s.  The project manager believes that it’s cost effective to get the engineer to do the PCB layout as well as the engineering.  After all, the engineer knows the design inside out, has some knowledge of Altium Designer and has designed a few PCB’s before. 

In most cases the final design will work but it may be of an average standard and generally takes twice as much time as it should. Some companies are willing to absorb this time cost. They don’t however, go to the next step and analyse and compare the costs of manufacturing "average" designs against great designs which take into account all the aspects of DFM.

For example, a professional PCB designer can potentially turn an eight layer PCB into a six layer PCB.  The price cost analyses below shows that there are considerable savings to be made for the manufacture of a board with fewer layers. It roughly costs 50% more to manufacture an eight layer board than a six layer board.

 

The above data was obtained from PCB Global (August 2014) however percentages will vary across different manufacturers so consult your own vendor for a price comparison. 

Reduced layers are one of many aspects of a great design that an experienced PCB designer can achieve. At Fine-Mark Design we get the best PCB outcomes for your projects. To contact Chris for more information about our service click the button below. 

Increasingly job descriptions require electronic engineers to have experience across many disciplines including hardware and software design and now even to utilize CAD software to layout PCBs.  For some engineers PCB design is the natural progression of the design process.  Others however, with limited CAD software experience find it difficult to get a great component placement not to mention then running thousands of tracks and also taking into account physical restrictions. There are many basic rules and good practices to follow however many would agree that PCB design is in fact a highly creative and individual process that takes passion, experience and talent.

Good design begins with the schematic

The PCB design process begins with the schematic diagram and generally engineers do a good job of creating a working schematic.  Before the actual design can commence a complete and thorough review needs to be done by an experienced PCB designer who will pick up and correct errors to ensure they are not carried on through to the design. Often a new set of eyes can identify errors that are otherwise continuously verified.  Engineers are not always experienced in driving PCB design software properly and some don’t utilize the electrical rule check (ERC) or the design rule check (DRC) features fully. 


Six common schematic diagram errors to avoid

1.    Miss spelling of net labels i.e. 0 used instead of O or I used instead of 1

2.   Power nets not matched across the whole schematic i.e. using +3.3V and then 3.3V in other instances.

3.    Component pins not connecting to desired wires therefore creating an open circuit.

4.    Not verifying all unused component pins i.e. sometimes they may need to be tied high or low for the device to operate properly.  

5.    Incorrect footprint assignments to components.

6.    Missing or extra junctions.

Most of the above errors can be easily identified if correct ERC procedures are carried out however it is surprising how often these small details are missed by the inexperienced CAD software user. 

At Fine-Mark Design we get the best PCB outcomes for your projects.  To contact Chris for more information about our service click on the button below.

By far the most important part of PCB design is component placement however inexperienced designers tend to rush this process.  Typically, 60% to 70% of the time spent on the design should be allocated to component placement.  It’s a bit like playing chess; you have to think several moves ahead otherwise you will have difficulty routing the board with the end result being poor electrical performance and possibly a board that cannot be manufactured. A well thought out component placement will allow for much better signal integration and in some cases allow you to even reduce the board layer count. 

General guidelines to producing a good component placement 

Firstly, layout the PCB outline on a mechanical layer and set the component grid to 25mil or larger. Load the components from the schematic into the work area.  At this stage you should be able to gauge if all the components will fit within your PCB area comfortably. If it appears that the density will be a problem do a density calculation.

Density Calculation

A density calculation needs to be done so that you know how tightly you have to place your components together to utilize the working area evenly across the board.  If the density is very high a tight component placement will be required.  If the density is over 80% the size of the PCB working area may need to be increased.  If the area cannot be increased consider the following options:

1.     Use smaller component F/P’s

2.     Place the components on both sides

3.     Remove circuitry which is not absolutely necessary

At this stage it is a good idea to divide the PCB working area into functional groups such as analogue, digital and power. If any isolation is required determine where you can allow for this to be placed now. 

Component Grouping

The next step is to group components as per functional schematic groups outside the work area of the board. During this procedure you should use the schematic as a guide and also switch on the connected nets in you PCB editor. Each functional schematic group will then be treated as a small PCB layout, where you will be arranging, rotating and placing components so that the track layout will be short and direct. In some cases you will need to refer to the PCB design guide lines of the particular devices that are used, eg. (Switch Mode Power Supplies) etc. You can also find actual recommended layouts that you should be able to reproduce.       
    
Don’t concern yourself too much about where the actual groups will go on the board yet.  Placement can be done of each group independently as each group can be treated as a small layout.  At this stage you can begin to route tracks within the groups as well. Once this is completed move, arrange and rotate the groups into your PCB area according to pre-determined functional groups. If you have placed your components and groups logically 70% to 80% of your design will be completed.  Then it’s just a matter of routing the nets between the groups.


Final Overview

When all the routing is completed do a design rule check (DRC) which will check for correct connectivity of tracks, widths and clearance.  Get someone to check your board because a fresh pair of eyes will pick up errors that have been overlooked. 

At Fine-Mark Design we get the best PCB outcomes for your projects.  To contact Chris for more information about our service click on the button below.
 

PCB design experts have thousands of hours invested in their experience and they are constantly updating their knowledge base.  PCB design takes a great deal of patience and aptitude to take the electronic schematic to a finished PCB which is ready for manufacturing.

The traditional route of “in-house” design may not always be viable if the project is running behind schedule and the time to complete the PCB design needs to be accelerated.  Also, most companies simply do have an PCB expert on hand to take care of complex designs.

Electronic development companies that engage the services of a PCB expert save time and money in the long run. Australian product development company Lockie Safety Systems usually designs PCB layouts in-house but when the company started a new project that required radically different architecture, it decided to engage an external expert. Read the results achieved in a tight time frame. CLICK HERE


At Fine-Mark Design we get the best PCB outcomes for your projects.  To contact Chris for more information about our service click on the button below.