# Transfer characteristic of this circuit

## Homework Statement:

What would be the input voltage and output voltage relation for input voltage values
1. -5<Vi<5
2. Vi<=-5
3. Vi>=5

## Relevant Equations:

V=IR
Assume constant voltage drop model Related Introductory Physics Homework Help News on Phys.org
Merlin3189
Homework Helper
Gold Member
I was trying to obtain a graph between the input and output voltage .

For the first case when input voltage vis between +5 and -5 volt I obtained the input voltage same as output voltage since the diodes will be reverse biased .

I just couldn't find the relation between these voltages when input voltage is below -5 V and above +5
So far so good.

When the input goes above +5 V, what happens to the diodes? Which one changes?
The diodes that are cut off (reversed bias) can be ignored as open cct. So draw what's left and see what you think will happen.

You need to show what you're doing and people will comment. When input is above 5V only this branch conducts because the diode will be forward biased . I tried using Kirchoffs voltage law to find the relation between input output voltages but for that i need current that is not given.

Merlin3189
Homework Helper
Gold Member
You could write a formula for the current in terms of Vi.
Then use that current to get a fromula for the output

Or an intuitive way is to ask, first, what if the battery and diode were shorted: what would Vout be then?
And if you put the battery back in, what difference does that make?
Then just add in the diode as well.

Edit: Maybe stick to the algebra! My intuition wasn't as good as I thought!

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