MEP EP #155: Void Copper Donuts

Podcast Notes

• Parker
  • Wagon Chime Module Repaired
  • StarWars Detonator Prop
  • RPI3 CM Motherboard USB Hub Saga
    • LAN9514
      • Page 14/15 of the datasheet
      • PRTCTL or Port Control
      • Single I/O that operates as a input and output
      • It operates as an open drain with an internal pullup
      • When the USB Power Switch senses an overcurrent it needs to drives the PRTCTL pin low
      • Then the LAN9514 also drives the pin low
      • This PRTCTL needs to operate the enable pin on the USB Power Switch
    • MP62551 or TPS2054B
      • Would need 4 MP62551 but I can provide 2A total verse 500mA
      • Operates the way the PRTCTL needs
      • Possibly breaking this HUB circuit into its own to prototype?
  • Improving the Prop Dev Stick
    • Changing to QFN from QFP Prop
    • 0402 parts instead of 0603
    • USB Type C for USB 2.0
    • Changing the power handling?
      • Original part is TPS2113
      • Only handles 5.5V MAX
      • NCP3901 is a Dual input Mux
        • Handles more power then I need but no built in current limiting
      • Maybe MPS has a good standalone current limiter?
• Stephen
  • Beginning the eq build. There is a lot to do so it is taking a bit of time
  • Gold fingers and connectors – They work!
  • Trying a special coax connection – Different rings on top and bottom
• R.F.O.
  • Bluetooth chip doesn’t need a battery because it harvests energy from the air
    • Wiliot
    • Embedded in consumer products to provide easy access to a digital manual when the original paper version is long lost, or it could be put on a clothing label and used to communicate the optimal settings to a washing machine
    • $30 million financing from Amazon and Samsung
    • Possible release in 2019 but they are shooting for 2020
  • HOWMAX30 – MAX-30 Single User Earplugs
    • Incorrect part listing on Amazon leads to hilarious reviews

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