Wednesday, 20 August 2014

design - Getting started with PCB designing


I'm a hobbyist EE in college, and have been building breadboard circuits and perfboard circuits for the past year or so. I want to move on to doing PCB design.


I wanted to start with something small so I designed a small amplifier circuit for a microphone that I want to make into a module on a PCB.



Here is the file for what I designed in Fritzing (I went with this software because it's user friendly): http://www.mediafire.com/?2b2as7iibys68cu


Here is an image if you don't have the program:


pcb


Is this a good design? How can I improve it?


The general schematic I followed was this (in case you wanted to know):


sch (Credit @Olin Lathrop)


What advice can you give me on getting started? Any resources you can recommend? What software would you recommend? Ideal would be free and easy to learn. What type of class would you suggest I take in college to get deeper into this?



Answer



I'll just comment on the design:




  1. Replace C5 with a 100nF ceramic capacitor and place it close to the power supply pin of the MCP6022.

  2. Put the designators on the PCB-Design, not values. Make it far easier to understand the layout.

  3. Avoid 90° trace bends, they can cause problems when etching the board. They're also bad for high-speed stuff (at least that's the common opinion on the matter). Use two 45° bends instead.

  4. Consider flooding one side of the board with a GND-Plane.

  5. Use wide short traces for power supply connections.

  6. Use one side of the board for mostly vertical traces and the other side for horizontal traces.

  7. Take more care of component placement. Place them in a way where they are easier to route. Component placement is 70% of the job. Place them BEFORE starting to route a single trace (Won't always work out). Just use the ratsnest (the lines which indicate connections which are not routed yet) as a rough guideline.

  8. Do not see a trace which is already routed as something which is fixed. If its in the way or you don't like they way it looks, rip it up and try again.

  9. When in doubt, start from scratch, try not to rescue something which can't be rescued anymore.

  10. Rule of thumb: Create something which pleases the eye. Others will have an easier time to understand it and sometimes it will even work better.



There are two Books i can highly recommend for learning Electronics/PCB Design: The Circuit Designer's Companion and EMC for Product Designers. While the second one more about EMC compliance it helps to understand WHY these things should be done in a certain way.


No comments:

Post a Comment

arduino - Can I use TI's cc2541 BLE as micro controller to perform operations/ processing instead of ATmega328P AU to save cost?

I am using arduino pro mini (which contains Atmega328p AU ) along with cc2541(HM-10) to process and transfer data over BLE to smartphone. I...