Skip to content

Lab 8

Lab #8

MOSFET BASICS

1. OBJECTIVES:

To introduce you to the Metal Oxide Semiconductor Field Effect Transistor (MOSFET).

2. COMPONENTS USED AND SPECIFICATION:

– BS170 MOSFET

– Several Resistors

– DC power supply

– Multimeter for voltage and current readings

– Waveform generator

– Oscilloscope with probes

– Computer with Multisim software for computer simulations

–  Wire, alligator clips, and a breadboard

3. DC Analysis:

lab 8_1

Figure 1

a) For the Figure 1 find the following:  VG, VD, VS, VDS, VGS, and ID.  Assume the MOSFET is in the Saturation region.  If the results turn out to be a contradiction, recalculate your results for the correct region.  Finally, state what region the MOSFET is in and your justification for your decision.  For your calculations use:  Vt = 1.824V, µnCoxW/L = 75.61mA/V2.

b) Assemble circuit as shown in Figure-1 (Rsig= 10KΩ, R1= 500KΩ, R2= 500KΩ, RD= 6KΩ, RS= 6KΩ, RL= 2KΩ, VDC= 15V, and all capacitors are very large) and measure the values (both software simulation and hardware).

4. AC Analysis:

lab 8_2

Figure 2

a) Calculate the AC analysis values using the T-Model shown in Figure 2.  Find RIN, ROUT, ro, gm, Avo, Av, and Gv.

b) Assemble circuit shown in Figure-1 (Rsig= 10KΩ, R1= 500KΩ, R2= 500KΩ, RD= 6KΩ, RS= 6KΩ, RL= 2KΩ, VDC= 15V, and all capacitors are very large) and measure the values (both software simulation and hardware).Set the sine wave generator to 50mVpp and 1KHz .Explain the discrepancy, if the measured gains are not within ± 0% of the calculated gains.

Lab report is individual and Analysis part should be on your own words.

The Lab report must include all lab procedures, all the observations from hardware and software simulations, and a detailed analysis.

Leave a comment

You must be logged in to post a comment.