MEP EP#331: The PCB Plague

MEP EP#331: The PCB Plague

Neutrik EtherCON Ruggedized RJ45

• Lockable RJ45 cable within an XLR style housing


• Also come in a sealed version that offers IP65 rating

Interesting PCB failures

• “The Plague”


• Black Pad


• Very poor to no solderability

Effect of Moon Phase on Tombstoning

• Many factors play a role in the overall outcome of PCB assembly, especially when very small components are involved. Broadly speaking, tombstoning is a problem with very small 2-pin components (0201 caps and such) and we've filtered out the following challenges:


• - proper paste application


• - component placement


• - designing for "good" thermal properties of the PCB with regard to tombstoning


• - moon phase

Stretching Stainless Stencils? Oddity Today

• Interesting manufacturing defect surfacing


• Stencil “stretches” ever couple panels or so


• Anyone ever seen or experienced this before?


• Solutions? Next Steps?

Project: SNACKEY

• Hacking a USI/Vendnet/FSI 3159


• Theory of how a snack machine works


• Interesting Parts
  
  
  • UCN5890A
  
  
  • UCN5842A
  
  
  • SC529136CFN2
  
  
  • M48T18-100PC1
  
  
  
  


• What I am doing to hack it
  
  
  • Motor control
    
    
    • High/Low side transistors
    
    
    • Might change this to mosfets to reduce voltage drop
    
    
    
    
  
  
  • Arduino all the things
  
  
  • Current sensing
    
    
    • INA219 High side sensing