Calculate the value of output voltage`V_(0)` and I if the Si diode and the Ge diode conduct at 0.7 V and 0.3V respectively, in the circuit given in Fig. If now Ge diode connections are reversed, what will be the new values of `V_(0)` and I.

Explanation

The effective forward voltage across Ge diode is `12V-0.3=11.7`
This will appear as the output voltage across the load, that is
`V_(0)=11.7V`
The current in the load is
`i=(V_(0))/(R_(L))=(11.7)/(5KOmega)=2.34mA`.
On reversing the connnections of Ge diode, it will be reverse-biased and conduct no current. Only Si diode will conduct. The effective forward voltage across Si diode is `12V-0.7V=11.3`
`V_(0)=11.3V`
The current in the load is
`i=(V_(0))/(R_(L))=(11.3)/(5kOmega)=2.26mA`.