Major mistakes in PCB Designing

[Altera_Forum]

"Hi, im new to PCB design. I want to avoid any major mistakes. Can I ask you guys 

a few questions?:)   1. What was your biggest 3 mistakes designing and why? 2. most popular software that you use and why 3. Biggest 3 frustrations about PCB design? 4. Biggest 3 fears (maybe related to PCB Assembly)?"  Your guidelines will be more helpful to proceed further.:D   Thanks

[Altera_Forum]

1. A. Not planning for proper clearance around components. 

B. Getting footprints for connectors correct on the board (mirroe images, pin sequencing 1-2 3-4 5-6 7-8  compared to 1 5 2 6 3 7 4 8  compared to  1 8 2 7 3 6 4 5  C. Not properly addressing clock traces and interference.  2. no comment 3. same 4. A. Initial power up!  B. Accidental shorting of power / Gnd while testing  C. That little puff of blue / grey smoke.

[Altera_Forum]

It's easy to overlook the jtag or configuration circuits. While they do run fairly slowly, a clock is a clock. When you've got the JTAG TCK routed all over the place it's easy to run into reflection problems. And a double-clock is bad even at 10 MHz. So it's good to think about the design a bit, buffer if needed, or at least put down a series termination. 

 Gregor

[Altera_Forum]

Yes, not giving enough attention to JTAG and config is a common problem. Check out this thread that has some pointers on JTAG... 

 http://www.alteraforum.com/forum/showthread.php?t=687

[Altera_Forum]

Thanks for you support everyone..!! :D  

  Regards,  S