Hi lin,
With D2 in circuit and D3 disconnected, what value do you calculate for V2 voltage.
This should enable you to determine if D3 will conduct, if it is connected.
E

 

Hi lin,
With D2 in circuit and D3 disconnected, what value do you calculate for V2 voltage.
This should enable you to determine if D3 will conduct, if it is connected.
E

without D3 branch, I calculate V2=-5-0.93*2.2=-7.046V, thus D3 is on , right?

 

hi lin,
As you have D2 connected, and it is conducting, it will increase the current through R2 and R3.
Don't forget the D2, 0.6V voltage drop from the 5V, when calculating the current through R2 and R3.
The voltage at V2 will indicate if the D3 diode is conducting.

As this is Homework, I cannot give you a complete answer.
E

 

without D3 branch, I calculate V2=-5-0.93*2.2=-7.046V, thus D3 is on , right?

If all sources are -5V, 0V, 5V and 10V, does it make sense to have a result that falls outside that range?

 

hi lin,
As you have D2 connected, and it is conducting, it will increase the current through R2 and R3.
Don't forget the D2, 0.6V voltage drop from the 5V, when calculating the current through R2 and R3.
The voltage at V2 will indicate if the D3 diode is conducting.

As this is Homework, I cannot give you a complete answer.
E

What is the key method to solve any multiple diodes circuits?

 

If all sources are -5V, 0V, 5V and 10V, does it make sense to have a result that falls outside that range?

what do you mean? my results make sense, right?

 

what do you mean? my results make sense, right?

Nope ...

The highest voltage source is +10V
The lowest voltage source is -5V
All sources are referenced to same potential - ground level or 0V and there are no current sources or storage elements (capacitors or inductors).; therefore ALL nodes in the circuit MUST have voltage that is either at one of those two extremes, OR in-between. There is no way to get -7V... It is outside of the bounds of the supplies.

 

Nope ...

The highest voltage source is +10V
The lowest voltage source is -5V
All sources are referenced to same potential - ground level or 0V and there are no current sources or storage elements (capacitors or inductors).; therefore ALL nodes in the circuit MUST have voltage that is either at one of those two extremes, OR in-between. There is no way to get -7V... It is outside of the bounds of the supplies.

Can you check this
View attachment 1747106622286.jpeg

 

What is the key method to solve any multiple diodes circuits?

Paying attention in the class or reading the course textbook... I