MacroFab Engineering Podcast

MacroFab's Engineering Podcast! Where Electrical Engineers, Parker Dillmann and Stephen Kraig talk about electrical engineering topics, DIY projects, and industry news. Sometimes cool people stop by the podcast to drop some knowledge.


episode 246: Doing Something Magical

MEP EP#246: Doing Something Magical

  • Physicists build circuit that generates clean, limitless power from graphene
    • University of Arkansas physicists
    • Energy harvesting the thermal motion of graphene
    • Without getting all quantum about it, it seems to work by configuring the graphene as one electrode (or both) of a capacitor. As the graphene flaps in the breeze (actually Brownian motion, I assume), the changing geometry will change the capacitance.
    • The team's next objective is to determine if the DC current can be stored in a capacitor for later use
    • Youtube video
  • New test equipment design - picking the right opamp
    • Current sensing with a bit of a twist
    • Powered by +/-12V
    • Need to read current on the +12 and the -12 along with a +9V rail
    • Opamp needs to be capable of reading a voltage drop in an environment where the common mode voltage is at or near the opamp supply voltage
    • Current sense amplifiers
    • INA1x9 series amplifiers from TI
      • Supply and common mode range are independent of each other
      • 2.7v to 60v
    • Convert a voltage to a current then change the gain by selecting an appropriate load
  • Iphone 12 doesn’t come with a charger?
    • Are chargers necessary?
    • Don't we have like 300 of them lying around?
    • Apple states environmental reasons for dropping the charger
    • Also no earbuds
    • Examples of other products that lack the equipment necessary to function
      • Video game consoles?
      • Appliances?
      • Internet router?