do powered diodes exist? diodes that can only operate the way they do because they use power to operate?

[jpoopdog]

Im just curious if such a technology exists, some sort of diode that perhaps requires electrical activation or something.

Not neccesarily to operate, since that would pretty much just be a fet or transistor then, but, some sort of significantly more effective diode, perhaps it can conduct more, has a much lower reverse voltage, much finer differential, or some other trait, amplified by a phenomena that requires power to work.

As an example, consider a simple speaker driver. On its own, it works, the line in goes directly to the speaker somehow (ignore the internal operations), so, it works in an unpowered state. Apply external power, and now it drives the speaker with considerably more volume.
Now im not neccesarily saying im looking for a diode that also works unpowered too like that, just one that can only work as well as it does because it consumes power in the process.

This would exclude though any sort of logic devices that actively switch a transistor or fet on/off in response to sensed voltage/current.


This isnt for any real world application im just curious if such a technology exists or existed. Dedicated to this sort of use, so not some sort of transistor rig that works this way.

Thanks

 

[dknguyen]

Not really except for diacs.

 

[jpoopdog]

that is close-ish, though an SCR uses a signal to switch on/off. and the signal moreso determines how it works, not how effectively.

 

[rjenkinsgb]

Some things do use "active rectifiers, basically replacing diodes with mosfets and a control circuit, to get around the normal forward drop of conventional diodes.

https://en.wikipedia.org/wiki/Active_rectification

There is no stand-alone device.

 

[unclejed613]

i'm not sure if this answers your question, but a vacuum tube diode doesn't work unless the filament has power applied to heat it up to a temperature high enough to create a space charge of free electrons (i'm not including gas diodes here, although an ignitron would also fit the description).

 

[unclejed613]

Now im not neccesarily saying im looking for a diode that also works unpowered too like that, just one that can only work as well as it does because it consumes power in the process.

technically any diode does consume power. for instance silicon diodes have a forward voltage drop of 0.7V. and if there's 1A forward current through the diode that's 700mW that the diode consumes, and radiates as heat.

 

[Nigel Goodwin]

Im just curious if such a technology exists, some sort of diode that perhaps requires electrical activation or something.

Not neccesarily to operate, since that would pretty much just be a fet or transistor then, but, some sort of significantly more effective diode, perhaps it can conduct more, has a much lower reverse voltage, much finer differential, or some other trait, amplified by a phenomena that requires power to work.

As an example, consider a simple speaker driver. On its own, it works, the line in goes directly to the speaker somehow (ignore the internal operations), so, it works in an unpowered state. Apply external power, and now it drives the speaker with considerably more volume.
Now im not neccesarily saying im looking for a diode that also works unpowered too like that, just one that can only work as well as it does because it consumes power in the process.

This would exclude though any sort of logic devices that actively switch a transistor or fet on/off in response to sensed voltage/current.


This isnt for any real world application im just curious if such a technology exists or existed. Dedicated to this sort of use, so not some sort of transistor rig that works this way.

Thanks

I can't make much sense of what you're actually asking?, but I suspect the answer is that you're looking for 'magic'.