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## Homework Statement

If the circuit shown, D2= 10 times the junction area of D1. What value of V results? To obtain V=50mV, what current I2 is needed?

## Homework Equations

i(D)=Is(e

^{VD/VT}-1)

## The Attempt at a Solution

I know junction area is related to diode current, so D2 has 10 times current as D1. But I still don't really know what to do. I tried KCL equation so 10/11mA -> 0.91mA going through D1. Then current thru D2 = 10*I(D1)=9.09mA this satisfies the KCL equation since 10mA is going on. But I didn't use the equation for diode current I listed so I have a feeling I did this all wrong. Then my other question is how does I2 determine V? It would help if I knew how to find voltage through the diodes but I don't want to assume that it is something like VD=0.7V. the problem didn't say anything about it neither.