1473149-4, 20-Band, CM3 Home, electronics podcast, EQ, i2c, Jeri Ellsworth, LAN9514, MacroFab, macrofab engineering podcast, Mobius Striptease, PCM5122, Reverse Polarity, Reverse Polarity Protection
Podcast
150

MEP EP #150: Connector Confusion

Podcast Notes

Congratulations to our Slack member Mobius Striptease! Mobius’ pulse generator won first place at their Senior Design Expo!

Article written about MacroFab: Houston electronics manufacturing company gears up for growth. Talks about the growth of MacroFab over the past 2 years.

  • Parker
    • RPI3 Compute Module
      • PCM5122 Routed
      • LAN9514 Routed
        • single upstream USB port on BCM2835
        • Pin 44 Ethernet 25MHz output
        • Pin 31 LAN RESET
        • Information found on the Raspberry pi forum
      • Need to add USB current limiting
      • CM3 HOME
        • Guido Ottaviani made his own carrier board I have been looking at for inspiration to solve some of the final problems
      • 1473149-4
        • Connector being used to socket the RPI3 Compute Module
  • Stephen
    • Crazy EQ amplifier design continuation
      • Opted to go with a card edge solution for each EQ band
      • Each band connects via a 36 pin PCI-Express connector
        • +12V
        • -12V
        • +5v Reference
        • -5V reference
        • Gnd
        • 4 In Signals
        • Cut
        • Boost
        • Potentiometer pin 2
      • 21 modules in total. 1 module has all of the power and main signal in/out from the amp. This sends all of the other modules their power/ground and signals.
      • Need to rethink things – Feedback loops are crappy.. Need to go with a 64 pin solution
        • 20 ins and 20 outs
    • Beveled edges and Hard Gold plating discussion in a future episode
  • R.F.O.
    • Debugging I²C with Hardware
      • I²CDriver is a crowdfunded effort by James Bowman
      • Open Source tool used to easily drive I2C devices
      • Controls with a GUI, command-line, C and C++ using a single source file, or Python 2 and 3, using a module
    • Low Cost Reverse Polarity and Over Current Protection
      • Jeri Ellsworth’s new video on reverse bias protection
      • Has a Robbie Robot on her desk!
      • Methods
        • “One of the options is to do nothing”
        • Diode input
        • Exploding Diode
        • PMOS FET
          • Low rds on – “almost not there”
          • Body Diode – Watch out for this

Visit our Public Slack Channel and join the conversation in between episodes!


Stephen's Amplifier rendered in Autodesk Fusion.

Stephen’s Amplifier rendered in Autodesk Fusion.

 

Underside of the amplifier. Not all the components are modeled yet.

Underside of the amplifier. Not all the components are modeled yet.

 

The current iteration of the 20 Band EQ module for the Amplifier.

The current iteration of the 20 Band EQ module for the Amplifier.

 

Close up the the PCI-Express connectors and slide pots.

Close up the the PCI-Express connectors and slide pots.

 

Almost looks like a heatsink!

Almost looks like a heatsink!


Special thanks to whixr over at Tymkrs for the intro and outro!