# PCB custom - tm4c12333h6pm

Previously, I tried to make a cusotm PCB with a tm4c123gh6pgei (https://electronics.stackexchange.com/questions/176117/tm4c123gh6pgei-custom-pcb)

After investigation of that PCB, I was able to observe that the JTAG communication occured but because of Faulty design , the MCU couldnt be programm.

Now, I am doing a second version with a smaller MCU tm4c12333h6pm ( 64 pins instead of 144).

My question is how to verify your PCB? Now, I followed more carefully the design PCB rule: putting VDDC cap and VDD cap very close to the MCU and much shorter JTAG line but still I feel like I doing a "blindshoot".

I got access to an Altium Designer license, can you use this software to verify the PCB implementation? How can you check that your PCB design is okay? Is it a empirical procedure or you can somehow check if a Design is flawed from the beginning?

Here is my PCB layout:

Here is my schematic layout:

I can send you the AD files if you have enough rep ( I just dont want to put in public the files)

[EDIT]

I went for 4 layers. Here is the new screenshoot:

• I don't mean to be mean, but your PCB layout is really bad. High speed (fast edge) signals like USB and your MCU require much better power distribution than your present design. I would recommend that you first brush up on your PCB design fundamentals before attempting to deal with the details of LVS, DRC, DFM and other manufacturing related verification steps. – DrFriedParts Jul 2 '15 at 20:26
• @DrFriedParts No, you aren't mean at all. The PCBS with high speed are really new for me. I am a beginner in that domain. What resources do you advice to improve my PCB skills? – MathieuL Jul 2 '15 at 20:27
• Yep, that's what I've come to expect from the auto-router ... – brhans Jul 2 '15 at 20:34
• @brhans Any tips? – MathieuL Jul 2 '15 at 20:35
• I like Dr. Johnson's book High Speed Digital Design. It is a nice middle ground between application and theory. I wrote a book on this topic too, but his is better ;) I've heard nice things about Chris Gammell's online course: contextualelectronics.com (but I've never actually reviewed it) – DrFriedParts Jul 2 '15 at 20:38

The key to make custom PCB is to :

1. Follow carefully the PCB guideline

2. Try to use 4 layers, using 4 layers make the overall design a lot easier because you don't need to worry about inductance on your power/ground.

3. Use software like Saturn PCB toolkit to calculate with efficiency your impedance width where you need to control impendance ( USB tracks).

4. Choose a manucfacturer that can let you have the right quantity of copper per inch/square

5. Take your time to carefully read the doc that concern sensitive part of your design, in my case it was the USB differential tracks.

6. Finaly, take to solder properly all your component.

These are the "major" guideline that I found out while doing the PCB. After I manufacturing the PCB, I ended up with a working PCB and where my USB got ported from the dev kit to a custom PCB.