Now we're going to talk about the most metal looks at semiconductor transistors, first the behavior and the current equations. So the transistor, the most transistor looks like this. It's a P sub-strait and you have N-type wells and on an oxide layer you have your gate. Source and drain. So what happens here is when you apply a voltage to gate you attract the electrons here and create an inversion layer and you have a current, is if you create a bridge here or we call it a channel and you can now conduct the current. And the transistor would look like this. This is your gate, this is your drain and this is your source. Because there is an oxide layer, there is no gate current and all the drain current would be equal to the source current. And the behavior would be the drain current. If you increase your gate source voltage, first you wouldn't get any current and then you start from beginning a current in exponential. And this part we would call it the threshold voltage. In terms of the idea versus VDS, if we increase, provided that the transistor is on, the transistor, the smaller the drain source voltages, the current would increase linearly and then reach to some sort of a saturation. So we call this triode region and this region, saturation region. So in triode region, you would have the, we just minus VTH, we also call this overdrive voltage. It would be bigger than drain source voltage. Here, you would have the current, you would have the VDS minus VTH, smaller than VDS. So we have a higher, larger VDS. And the current equation for the triode region would be a function of not only transistors, gate source voltage, but also drain source voltage. So drain source and also gate source voltage. W over L are your transistors dimensions with N length and this is a process specific parameters. So in saturation, you would have mostly the VGS dependence. So there is not much drain source voltage dependence. However, just like the NPN transistor, we have a parameter here, this lambda, that comes from that's called the channel length modulation. That affects the transistors behavior and adds as a drain source voltage dependence.