Published: Oct. 14, 2020, 10:46 p.m.
Parker
- 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
Stephen
- 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?
