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I am studying electronics independently, so this question is perhaps obvious for an engineering student.

I know that, for the ALD1106 MOSFET, we can assume a typical \$V_t = 0.7 V\$. How could I design a circuit to calculate the component's \$K\$ and \$\lambda\$ parameters analytically?

To force a saturation behavior, I will assume that \$V_{DD} = 5V\$ and \$I_D = 500 μA\$.

schematic

nickh
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  • Look at the common circuits that are used to **characterize a MOSFET**, for example: https://www.electronics-tutorials.ws/amplifier/mosfet-amplifier.html and http://www.billhung.net/ee105/Lab04.htm *I will assume that VDD=5V and ID=500μA.* OK, nice but suppose you apply that VDD=5V to the MOSFET and only 10 uA is flowing, what are you going to do about it? – Bimpelrekkie Oct 08 '20 at 11:21
  • Thank you for the sources, I will take a better look at them now. Just to answer your question, I assumed VDD=5V and ID=500μA to lower the number of degrees of freedom. I am not saying that the analysis will be broad (i.e for any resistance values in the drain), my objective is to determine lambda and K with a saturated NMOS with those values of ID and VDD – nickh Oct 08 '20 at 11:56
  • *I assumed VDD=5V and ID=500μA to lower the number of degrees of freedom* Sure but the MOSFET will not "read your mind" and make that 500 uA flow. You have to convince the MOSFET to conduct just so much that there's actually 500 uA flowing. You have to give Vgs the right value for that to happen. Note how in the characterization circuits, there's a variable voltage source that sets Vgs. – Bimpelrekkie Oct 08 '20 at 12:32
  • Ok, I got it now. If want Id = K(Vgs - Vt)² = 500uA, then Vgs should be set appropriately. But now I don't have enough information to determine K (which should be a constant). Perhaps I am missing something here... – nickh Oct 08 '20 at 12:48
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    @N.H.Deutschland What do you normally do when you have two unknowns to solve? For example, in a diode there are three important parameters when temperature is ignored. The saturation current, the emission coefficient, and the bulk resistance. So I take three measurements. – jonk Oct 08 '20 at 13:07
  • https://electronics.stackexchange.com/questions/298829/common-drain-jfet-output-resistance-problem/299030#299030 and this https://www.ti.com/lit/ml/slup170/slup170.pdf?ts=1602162534653&ref_url=https%253A%252F%252Fwww.google.pl%252F – G36 Oct 08 '20 at 13:14

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