Begin with a value of VGG 0 volts by adjusting the DC suppl

Begin with a value of V_GG = 0 volts by adjusting the DC supply to zero volts, and adjust the V_DD supply to 5 volts. Verify that the LED is off. Adjust V_GG to a positive voltage equal to approximately 2.0-2.: volts; verify that this causes the LED to just begin to turn on. (If this does not happen, consider reversing the polarity of the LED.) Continue to increase V_GG to increase the intensity of the LED, to a maximum value of about 3.5 volts. The LED current will reach a maximum which results when the MOSKFET is fully \"turned on\" (i.e., when the point on the load line reaches the \"ohmic region\" of the MOSFET). Further increases in V_GG should not result in increases in LED intensity Configure the multimeter as an ammeter to measure the current flowing into the gate change with gate voltage?

Solution

Spice Simulation 1-1

*** MODEL Descriptions ***

.model nm NMOS level=2 VT0=0.7

KP=80e-6 LAMBDA=0.01

*** NETLIST Description ***

M1 vdd ng 0 0 nm W=3u L=3u

R1 in ng 50

Vdd vdd 0 5

Vin in 0 2.5

*** SIMULATION Commands ***

.op .end