MEP EP#45: Zero Sum Resistor Arrays

Parker Dillmann |   |  Apollo 10, Bluetooth 5, Jeep Radio, MacroFab, MEP, Podcast, Resistor Standard, Samsung Battery, TDA7340S, Zero Ohm Resistor

MacroFab Engineering Podcast

Stream:

Download: MP3
RSS Feed: Link

Runtime: (27:54)

Hosts:
Parker Dillmann
Stephen Kraig

Guests:
N/A


Figure 1: Opamp audio level shifter for the Jeep Bluetooth project.
Figure 1: Opamp audio level shifter for the Jeep Bluetooth project.

Podcast Notes

  • Parker has a new update to the Jeep Bluetooth Radio Mod. To level shift the Bluetooth audio to what the TDA7340S expects, Parker is going to build a differential opamp. The Bluetooth audio adapter has a 50mV DC offset and a 1.9V Pk-Pk at max volume where the TDA7429L is expecting a 4.65V DC offset with a 800mV Pk-Pk. See Figure 1.
  • Stephen has a crazy idea to make the “ultimate” inexpensive resistor standard. His plan is to use a big array of resistors that are in parallel/series. He hopes that statistically it will swamp out the tolerance. Stephen will use different manufactures to swamp out batch issues. Next week we should have some analysis on this project done.
  • Analog-EETimes article: Why the zero-ohm resistor?
  • NASA Wants SpacePoop Hackers. Reminds Parker of this Apollo 10 radio transcription. See page 416.
  • New Bluetooth 5 spec is out. Key updates to Bluetooth 5 include longer range, faster speed, and larger broadcast message capacity.
  • Samsung exploding battery update.

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