Answer / prashant sharma

device which are capable of controlling electrical flow by the use of other electrical quantity(current or voltage)are called active device.
also actice devices have property of giving direction to electric flow and amplify the signal....
Thus, diode in not a active device(its a passive one) since
1)no external supply is provided for the electric flow control
2)do not amplify the signal...

Answer / priyanka verma

It depends on what type of a diode you mean.
In most cases (rectifier, Zener, etc.) a diode is,
no doubt, a PASSIVE device.
Only in some special cases like with a tunnel diode,
when its negative resistance region is used, it can be considered as an ACTIVE device.

Answer / savinmurali

diode is a passive component....... which is having p-n
junction.... reaction starts only when source is applied.
please correct me if i am wrong

Answer / sandeep rawat

diode is a active device. active devices are those which
have ability to supply energy or which have ability to
create potential difference.
in diode there is built in potential across depletion region
known as contact potential . so diode acts as a battery
having voltage of magnitude equal to contact potential.

Answer / fazley rafy

I've heard various definitions of passive and active device.They are:

1.Active devices can generate Power but passive devices can't.

Here can BJT alone be termed as a active device or BJT in the amplifier config. is termed as a active device?

2.If a device can control carrier by means of another electrical signal,it's calle active device.

3.One prof. of mine told me,on asking that the classification of diode being active and passive changes depending on whether we see it from Electronics Engg point of view or Electrical Engg point of view.He went to explain that in Electrical Engg.,diodes are mostly used as rectification devices and thus are passive
But from Electronics Engg. point of view,diodes are used as both oscillators and rectifiers and other wave shaping Page on Purposes it can be both active or passive

I see that both first and second statements mean the same.But the contentious device is the diode.

It acts as passive device from first definition,but by second definition it should be an active device as the voltage across it controls carrier flow.

Also some varieties like the Tunnel Diode and Gunn Diode are used as oscillator.So by both first and second definition,these are active device.

So what exactly all this active and passive stuff.I'm totally confused.
Can someone please clear all the fuss and PRECISELY DEFINE ACTIVE and PASSIVE nature.

Answer / pragna

deviec which can amplify ---active element eg BJT,FET,OPAMP
device which cannot amplify --passive element eg PN diode,resistor,L ,C
list is endless...

Answer / reshma

diode is a passive device since current flows through it!

Answer / ram

Diode is a passive component it won't required any source.

Answer / farhad ali(b.e in clectronics

IT IS PASSIVE because it doesn't need sorce

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