Question

Notify Me Bookmark

The iD−vGS characteristics of the MOSFET transistor in saturation are plotted below for the enhancement-mode and depletion-mode NMOS and PMOS devices. For each curve, write down the conduction type (either NMOS or PMOS) and the mode (enhancement or depletion) of the device. (1)type: mode: (2) type: mode: (3) type: mode: (4) type: mode:

The iD−vGS characteristics of the MOSFET transistor in saturation are plotted below for the enhancement-mode and depletion-mode NMOS and PMOS devices. For each curve, write down the conduction type (either NMOS or PMOS) and the mode (enhancement or depletion) of the device. (1)type: mode: (2) type: mode: (3) type: mode: (4) type: mode:

Image text
  1. The i D − v G S characteristics of the MOSFET transistor in saturation are plotted below for the enhancement-mode and depletion-mode NMOS and PMOS devices. For each curve, write down the conduction type (either NMOS or PMOS) and the mode (enhancement or depletion) of the device. (1)type: mode: (2) type: mode: (3) type: mode: (4) type: mode:

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

Consider MOSFET-based current source circuits shown below. Assume that the n-type MOSFET transistors follow the long-channel model with μnCox = 100 μA/V2 and Vth,n = 0.5 V. All the transistors have a fixed channel length L = 0.25 μm. The bias voltage VB1 is at 0.8 V. Assume that all transistors have no back-bias effect. (1) (2) (a) For a basic current source in Fig. (1), size the NMOS transistor M1's width ( = W1) so that it conducts a current of 1 mA when it operates in saturation region. You may assume λn = 0. (b) What is the minimum value of Vout for this circuit that keeps M1 in saturation region? (c) For a cascode current source in Fig. (2), assume that the transistor M2 has the same width with M1 you determined from part (a). Determine the value of VB2 that yields the lowest minimum VOUT keeping both M1 and M2 in saturation regions. (d) Now, let's assume that the transistors M1 and M2 have a finite output resistance with λn = 0.1 V−1. Compute the value of the output resistance (Rout) of this cascode current source when M1 and M2 are in the saturation region. (Hint: Calculate the output impedance in a small signal equivalent circuit.)
Solution
0 0

For the amplifier below, following design information is provided: VDD = 3.3 V, R = 2.4 kΩ, ISS = 1.8 mA, k1 = k2 = 5 mA/V2, VTH,1 = VTH,2 = 0.5 V, λ = 0.1 V−1, γ = 0, ki′ = μ0Cox, ki = μ0 Cox(W L)i. Assume that both transistors are identical and in the saturation region. Finally, NMOS and PMOS bulk terminals are connected to the ground and VDD, respectively. a) What is the DC bias voltage for M1 and M2 given that the voltage drop across ISS is 0.4 V ? You can neglect the channel length modulation, here. Check that the transistors are in the correct operation-mode. b) The resistors will be realized using identical PMOS transistors M3 and M4. If the transistors to be used will have k3 = k4 = 1.5 mA/V2, what will be their overdrive voltages? Check that the transistors are in the correct operation-mode. c) What is the differential voltage gain AV,diff = Vout/Vid in dB ? d) ISS will be realized as a cascode current source. Assume that the voltage drop of 0.4 V is equally shared by the two transistors, M5 and M6 having k5′ = k6′ = 0.5 mA/V2 and VTH, 5 = VTH, 6 = 0.5 V. Assuming the gate voltages of both transistors are 1 V, find the W/L ratios of each device. Once again, you can neglect the channel length modulation here. e) Considering (d), how would the W/L ratios qualitatively change (increase/decrease/stays the same), if γ > 0 ? Explain your reasoning analytically, i. e. , using appropriate equations. f) Using the cascode current source, calculate the common-mode gain of the circuit AV, CM = Vout /Vin in dB, where Vin . s applied to the gates of both M1 and M2. Assume λ = 0.1 V−1 for M5 and M6. g) Calculate the CMRR of the circuit in dB.
Solution
0 0

Transient Point (Threshold Voltage) In practice, in an inverter circuit, there is an unstable transient point at which both transistors are on and in saturation mode. The input voltage (connected to the gate) for this point is called the threshold voltage (Vin = VTH). At this point, VGS/VSG of the NMOS / PMOS is equal to Vin/VDD-Vin. Note that this threshold voltage is different from the intrinsic threshold voltage of transistors (VTN or VTP). Derive an expression for this threshold voltage [RP2]. Verify your work with the expression below: What happens to VTH when Kp > Kn, Kp = Kn, and Kp < Kn? What haapens when Kp approaches 0 or when Kn approaches 0? Use words to generalize how various Kn and Kp values change VTH and describe how the values of Kn and Kp can be tuned by parallel MOSFET connection [RP2]. Noise Margin Please read section 6.9.4 of the textbook or search on the internet about noise margin. Sketch a typical transfer function of an inverter (non-ideal one) with 1 PMOS and 1 NMOS and label VIL, VOH, VOL,VIH, NMH, and NML on your sketch [RP3]. Why is the metric of noise margin useful [RP3]? Make a reasoned guess about how the change in the threshold voltage VTH (or the change in Kn/Kp ) affects each of the noise margin parameters [RP4].

Transient Point (Threshold Voltage) In practice, in an inverter circuit, there is an unstable transient point at which both transistors are on and in saturation mode. The input voltage (connected to the gate) for this point is called the threshold voltage (Vin = VTH). At this point, VGS/VSG of the NMOS / PMOS is equal to Vin/VDD-Vin. Note that this threshold voltage is different from the intrinsic threshold voltage of transistors (VTN or VTP). Derive an expression for this threshold voltage [RP2]. Verify your work with the expression below: What happens to VTH when Kp > Kn, Kp = Kn, and Kp < Kn? What haapens when Kp approaches 0 or when Kn approaches 0? Use words to generalize how various Kn and Kp values change VTH and describe how the values of Kn and Kp can be tuned by parallel MOSFET connection [RP2]. Noise Margin Please read section 6.9.4 of the textbook or search on the internet about noise margin. Sketch a typical transfer function of an inverter (non-ideal one) with 1 PMOS and 1 NMOS and label VIL, VOH, VOL,VIH, NMH, and NML on your sketch [RP3]. Why is the metric of noise margin useful [RP3]? Make a reasoned guess about how the change in the threshold voltage VTH (or the change in Kn/Kp ) affects each of the noise margin parameters [RP4].
Solution
0 0