ZENER BREAKDOWN has caused me a breakdown

**sudar_dhoni** · Nov20-09, 12:27 PM

could any1 plz explain avalance effect
i can understand that the electrons minority carriers are accelerated by high voltage and collide with valence electrons break free them and what happens after that
do they all go back to the positive terminal plz explain after the production of avalanche of electrons

**sokrates** · Nov22-09, 11:30 AM

The newly liberated electrons, provided they have enough energy, do the same to other stationary electrons.

Hence the term avalanche.

**sudar_dhoni** · Nov23-09, 06:06 AM

Originally Posted by sokrates

The newly liberated electrons, provided they have enough energy, do the same to other stationary electrons.

Hence the term avalanche.

after that what will happen thats what my question

**sokrates** · Nov24-09, 02:26 PM

you'll observe high amounts of current at the external circuit.

**sudar_dhoni** · Nov25-09, 05:08 AM

Originally Posted by sokrates

you'll observe high amounts of current at the external circuit.

ok high amount of current will flow from the n type to the + terminal
but then who will fill the holes caused now in the n type due to collision by the minority carriers on the valence band electrons of n type
those places will be vacant and there will be holes in n type what will happen next????

**Naty1** · Nov25-09, 09:01 AM

Unsure from your wording exactly what's bothering you, you seem to be questioning both the avalanche effect itself and then what happens after that when the Zener diode is switched on....but free electrons drift in a circuit with a zener diode just like any another other circuit, filling holes .

Try: http://en.wikipedia.org/wiki/Electrical_current for a general discussion

Also try here, it seems applicable to your concerns:
http://en.wikipedia.org/wiki/Zener_diode

**sudar_dhoni** · Nov25-09, 09:57 AM

Originally Posted by Naty1

Unsure from your wording exactly what's bothering you, you seem to be questioning both the avalanche effect itself and then what happens after that when the Zener diode is switched on....but free electrons drift in a circuit with a zener diode just like any another other circuit, filling holes .

Try: http://en.wikipedia.org/wiki/Electrical_current for a general discussion

Also try here, it seems applicable to your concerns:
http://en.wikipedia.org/wiki/Zener_diode

ok i 'll come straight to the point now
plz explain the flow of electrons through the entire circuit till it completes one cycle in
1) avalanche breakdown
2) zener breakdown

**sokrates** · Nov25-09, 11:58 AM

I don't know where you are going with this.

There are far too many electrons around, to fill those "vacancies" in extremely fast timescales.

Is there any experimental or theoretical motivation behind all this?

Or are you just feeding your curiosity?

There are effects like "source starvation" observed in small devices where the source cannot supply enough electrons to the circuit, and all that is seen by a decrease in current.

But such a thing will NEVER happen in a Avalanche breakdown mechanism, because you are NOT budging the CORE electrons at ALL ! Ripping a few outer shell electrons and seeing a large current is all you see. Before you can rip the core electrons, you'd need much greater voltages and by that time you'd have burned up your whole circuit anyway...

**sudar_dhoni** · Nov25-09, 09:26 PM

Originally Posted by sokrates

I don't know where you are going with this.

There are far too many electrons around, to fill those "vacancies" in extremely fast timescales.

Is there any experimental or theoretical motivation behind all this?

Or are you just feeding your curiosity?

There are effects like "source starvation" observed in small devices where the source cannot supply enough electrons to the circuit, and all that is seen by a decrease in current.

But such a thing will NEVER happen in a Avalanche breakdown mechanism, because you are NOT budging the CORE electrons at ALL ! Ripping a few outer shell electrons and seeing a large current is all you see. Before you can rip the core electrons, you'd need much greater voltages and by that time you'd have burned up your whole circuit anyway...

ok then explain zener diode and zener breakdown
how there it does not happen what happens in avalanche breakdown
in both the same will happen
but in zener diode what special will happen which does not happen in avalanche breakdown