How to draw Load Lines?

[fouadalnoor]

Hey guys,

I know this is pretty simple, but I just can't get the full intuition for it. If you look at the attached picture, my lecturer simply drew the load line going from Vb/R to Vb.

I kinda understand how he did it (he is simply drawing the VI characteristic of the resistor) but I want to get it in the maths as well.

Can one of you guys show me the math's steps one at a time so I know exactly how he did it (he got a straight line equation of the form y=-mx+c)

 

[Diver300]

The load line show what how the resistor and the supply behaves. The load line does not depend on the diode characteristics at all.

The graph is drawn as current as a function of voltage. The current at zero voltage is VB/R, which is simply Ohms law.

The slope of the graph is -1/R. With each Volt increase, there is a Volt less drop across the resistor, so 1/R less current.

That gives a graph of I = VB/R - V/R

 

[fouadalnoor]

Thanks! I think I get it now since got the same equation that he got. I think sometimes I over think simple things which kinda confuses me.