Question

Notify Me Bookmark

Consider the MOSFET amplifier circuit below. Assume that the transistor is in saturation mode, ignore ro and a) Draw the small-signal circuit of the amplifier using the MOSFET pi-model and the T-model. b) Derive an expression for the voltage gain. c) Derive an expression for the overall voltage gain. d) Derive an expression for the current gain. e) Find the amplifier input resistance. f) Find the amplifier output resistance. g) Based on your results, does this circuit serve as a "good" voltage amplifier or as a "good" current amplifier? Explain.

Consider the MOSFET amplifier circuit below. Assume that the transistor is in saturation mode, ignore ro and a) Draw the small-signal circuit of the amplifier using the MOSFET pi-model and the T-model. b) Derive an expression for the voltage gain. c) Derive an expression for the overall voltage gain. d) Derive an expression for the current gain. e) Find the amplifier input resistance. f) Find the amplifier output resistance. g) Based on your results, does this circuit serve as a "good" voltage amplifier or as a "good" current amplifier? Explain.

Image text
  1. (40 points) Consider the MOSFET amplifier circuit below. Assume that the transistor is in saturation mode, ignore r o and a) Draw the small-signal circuit of the amplifier using the MOSFET pi-model and the T-model. b) Derive an expression for the voltage gain. c) Derive an expression for the overall voltage gain. d) Derive an expression for the current gain. e) Find the amplifier input resistance. f) Find the amplifier output resistance. g) Based on your results, does this circuit serve as a "good" voltage amplifier or as a "good" current amplifier? Explain.

Detailed Answer

0 0

Please enter your email here. You will get email when this question is answered by our tutor.

Doubtrix Logo

Problem is not yet solved!

Click on Notify me to get email when question is answered.

Join Doubtrix with 7-days free trial

  • Icon Correct & Verified Answers
  • Icon No AI-Generated Answers
  • Icon Video Solution for Difficult Questions
  • Icon Work With Experts to Reach at Correct Answers
Notify me Login Sign Up

Similar/Related Questions

For the amplifier circuit below, with the transistor in active mod ignore ro ? and, a) Draw the amplifier equivalent circuit using the pi-model. b) Find the amplifier voltage gain. c) Find the overall amplifier voltage gain. d) Find the amplifier input resistance. e) Find the amplifier output resistance. f) Find the amplifier current gain. g) What is the amplifier type? Do your results confirm the amplifier type? Explain.
Solution
0 0

Exercise 8.4 Consider the MOSFET amplifier shown in Figure 8.3. Assume that the amplifier is operated under the saturation discipline. In its saturation region, the MOSFET is characterized by the equation iDS = K 2 (vGS − VT)2 where iDS is the drain-to-source current when a voltage vGS is applied across its gate-to-source terminals. Figure 8.3: a) Write an expression relating vO to vI. What is its operating point output voltage VO, given an input operating point voltage of VI ? What is the corresponding operating point current IDS ? b) Assuming an operating point input voltage of VI, derive the expression relating the small signal output voltage vo to the small signal input vi from the relationship between vO and vI. What is the small signal gain of the amplifier at the input operating point of VI ? c) Draw the small signal equivalent circuit for the amplifier based on the SCS model of the MOSFET assuming the operating point input voltage is VI. d) Derive an expression for the small signal gain of the amplifier from the small signal equivalent circuit. Verify that the gain computed from the small signal equivalent circuit is identical to the gain computed in part (b). e) By what factor must RL change to double the small signal gain of the amplifier? What is the corresponding change in the output bias voltage? f) By what factor must VI change to double the small signal gain of the amplifier? What is the corresponding change in the output bias voltage?
Solution
0 0

Consider the circuit configuration shown below, which is commonly used for measuring n-channel MOSFET parameters. The transistor's length and width are 1 μm. The accompanying graph plots the transistor's square root of drain current vs. gate voltage, VG. a) Estimate the threshold voltage of the n-channel MOSFET. b) When VG is between 1.5 V and 2.5 V, in what region is the device operating? Consider the p-channel MOSFET amplifier given to the right. ID = 12 kp(VSG − |Vtp|)2, VDD = 5 V, RL = 2 kΩ, kp = 1 mA/V2, Vtp = −1 V c) Derive an expression for the transistor bias point, VGQ, as a function of VDD, Ra, and Rb. d) Determine the required ratio Ra/Rb such that the MOSFET current, ID = 0.5 mA e) What is the voltage bias point of the output VoutQ? Use the value(s) from part d. Please show all steps. A_ = 0.5 VB = Saturation C = VoD(Rb/(Ra+Rb))D = Ra/Rb = 2/3 E = 1 V)

Solution
0 0