# Homework Help: Transistor analysis

1. Nov 1, 2011

### sandy.bridge

1. The problem statement, all variables and given/known data
Just started learning about transistors, and I am having difficulty doing this problem.

The transistor in the circuit has $$k_n ^'=0.5mA/V^2, V_t=0.5 V, \lambda =0.$$
Show that operation at the edge of saturation is obtained when the following condition is satisfied
$$(\frac{W}{L})R_D=1.5 kΩ$$

3. The attempt at a solution
As far as I know, if it is operating in on the edge of saturation, then
$$\frac{1}{2}k_m ^'(\frac{W}{L})v_{OV}$$
However, when I manipulate this equation, I am unable to get to $$(\frac{W}{L})R_D=1.5 kΩ$$

Can anyone provide me some guidance on this?

2. Nov 2, 2011

### sandy.bridge

Thanks anyways, but I figured it out.

3. Apr 28, 2012

### _Jethro_

Hi, I'm bumping this old post because I am currently trying to work through the same problem but can't quite figure it out. I have the same equations that were mentioned in the original post.

Any guidance would be appreciated.