# Maximum input voltage a diode can handle

#### hoyyoth

Joined Mar 21, 2020
18
Dear Team,

May I know how to find the maximum input voltage a didode can handle.I checked many datasheets no info about this.

Can I apply any voltage greater than it's forward voltage.

Regards
HARI

#### SamR

Joined Mar 19, 2019
2,809
Just which diode? Here is a typical which shows max V.

The Vf for a silicon diode is ~0.7V, so of course you can provide greater voltage, or else it won't conduct at all. But if you provide a voltage higher than the Peak Reverse or max RMS you will burn it out. Another thing you need to look at is the power rating. If you take the max V and max I for a diode and convert that to Watts you will be far above what the diode can handle. So you have to look at the Voltage, Current, and Power ratings of the component when choosing it.

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#### hoyyoth

Joined Mar 21, 2020
18
Just which diode? Here is a typical which shows max V.
View attachment 220042
The Vf for a silicon diode is ~0.7V, so of course you can provide greater voltage, or else it won't conduct at all. But if you provide a voltage higher than the Peak Reverse or max RMS you will burn it out.
Hi Sam,

Thank you very much for the clarification.
Now it is clear .

Regards
HARI

#### Marc Sugrue

Joined Jan 19, 2018
167
Dear Team,

May I know how to find the maximum input voltage a didode can handle.I checked many datasheets no info about this.

Can I apply any voltage greater than it's forward voltage.

Regards
HARI
When you pass a forward biased current through a diode the forward votage can range between 0.4 & 1.2V this will be dependant on the type of Diode (Rectifier, Schottky etc) and the amount of current you pass through it - it is impossible to place a sustained voltage accross a diode greater than its voltage drop in its forward biased condition - this voltage is defined by its current.

For maximum voltage you would be referring to the maximum reverse voltage which would be the device rating as described in post #2.

#### MisterBill2

Joined Jan 23, 2018
7,320
There is indeed a process for determining the reverse breakdown voltage of a diode, but it often involves hazardous voltages, and always includes the possibility of doing damage.
The actual definition of the peak reverse voltage is that reverse bias voltage at which the leakage current starts to increase past some limit. The limit depends on the type and application of the diode.

#### BobTPH

Joined Jun 5, 2013
2,601
If ypu apply a 2V supply with 100A capability you can kiss your diode goodbye (for any diode you can afford.)

Bob

#### dl324

Joined Mar 30, 2015
11,914
Thank you very much for the clarification.
Now it is clear .
Maximum power dissipation is the limiter. You don't want the junction to get hot enough to melt.

That will depend on forward voltage, current, ambient temperature, heatsinking, the thermal resistance of the package, ...

#### MisterBill2

Joined Jan 23, 2018
7,320
If ypu apply a 2V supply with 100A capability you can kiss your diode goodbye (for any diode you can afford.)

Bob
That is the forward voltage drop. I was talking about the reverse voltage leakage. THAT voltage is what is called the reverse voltage.

#### hoyyoth

Joined Mar 21, 2020
18
Dear All,

Thank you very much.

Regards
HARI

#### BobTPH

Joined Jun 5, 2013
2,601
That is the forward voltage drop. I was talking about the reverse voltage leakage. THAT voltage is what is called the reverse voltage.
But that is not what the TS was asking about. He asked if he could aplly any voltage greater than the forward voltage.

Bob

#### MisterBill2

Joined Jan 23, 2018
7,320
Dear Team,

May I know how to find the maximum input voltage a didode can handle.I checked many datasheets no info about this.

Can I apply any voltage greater than it's forward voltage.

Regards
HARI
It is not clear why you are asking this question. The purpose of a diode is to prevent current from flowing in the reverse direction. The exact forward voltage drop is dependent on the temperature of the diode junction. Oer are you asking about the maximum reverse voltage? Mostly folks are concerned with thee maximum forward current and the peak reverse voltage.
So what is your application that you are asking about applying a voltage in the forward direction? I have not come across such an application is why I am asking.

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