# Homework Help: Diode circuit analysis

1. Nov 18, 2014

### woohs1216

< Mentor Note -- Thread moved to Homework Help from EE forum >

hi guys

I am studying on diode circuit but i cannot really analyse a circuit with a diode.
I understand that the question is asking minimum Vout so the current source input should be -2.5mA but i cannot go beyond that.

Can anyone help me on this question?

Last edited by a moderator: Nov 18, 2014
2. Nov 18, 2014

### Staff: Mentor

Hi woohs1216. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif [Broken]

I think you should take a sheet of paper, turn it in landscape mode, and draw 1 cycle of a large sinewave. This can represent Iin. Mark half a dozen points on that sinewave and then for each of these current values analyse the circuit determining those parameters of interest that will help you in plotting Vout and finally being able to answer the question.

Remember, the diode does not conduct current in one direction, and in the other direction it does conduct but has 0.8v across its terminals while it is conducting current.

Last edited by a moderator: May 7, 2017
3. Nov 18, 2014

### rude man

Right, minimum output voltage occurs when iin = -2.5 mA.
What is the diode doing then?
What is the voltage at the resistor?
Finally, what is the output voltage?