Hi, I am working on a logic unit (I know they already exist, I like to do things the hard way). One thing that I am unsure about is ampere logic. A diode only permits electricity to pass in 1 direction, but will not begin conducting until the voltage across it hits a certain value. Is there something that doesn't begin conducting until the current (mA) across it hit a certain value? A transistor is one option, but the problem with that is that it can take very high amounts of energy in the collector, and will short if too much energy is applied. Thanks!