3 ms·

cf the story of the first ARM dev board running off leakage without any direct current. https://www.theregister.com/Print/2012/05/03/unsung_heroes_of_tech_arm_

cf the story of the first ARM dev board running off leakage without any direct current. https://www.theregister.com/Print/2012/05/03/unsung_heroes_of_tech_arm_creators_sophie_wilson_and_steve_furber/ https://www.theregister.com/Print/2012/05/03/unsung_heroes_o... “The development board plugged the chip into had a fault: there was no current being sent down the power supply lines at all. The processor was actually running on leakage from the logic circuits. So the low-power big thing that the ARM is most valued for today, the reason that it's on all your mobile phones, was a complete accident."

rcxdude 4y ago
This is a trick a lot of ICs are quite good at: because of the protection diodes on the inputs and outputs of most chips, voltage on the pins will also pull the internal power of the chip up if the power pins are not energised. A lot of chips will run quite happily like this until either all the IO pins supplying power go low or the IC draws enough current to damage the diodes (which aren't generally designed to continously conduct). I have on one occasion had a power IC (stepper motor driver) manage the same trick for a few minutes, which was very unusual and made debugging a lot harder (because of course the power pins are connected, it was running just a few minutes ago!)