Shlapenka wrote on Nov 20th, 2009, 7:25am:Greetings,
what makes a MOSFET transistor act as a resistor? Is it W>L (W lenght more than L lenght)?
Each FET, indeed, is a resistor!
It consists of a channel which can lead an electrical current if you apply a voltage across the channel - and that,by definition, is a resistance.
The only (but important) difference to an ohmic resistor is the fact, that there is a quasi-linear relationship between voltage and current only within a limited voltage range (some tenth of volts around zero).
More than that, the value of this resistance can be controlled with the gate voltage.