The MOSFET in the circuit shown has threshold voltage Vt = 2.5 V and rSD(on) = 0.29 Ω. The motor can be represented in DC as a resistance RM = 4.9 Ω and VDD = 3.2 V. a. Compute ID in mA when the MOSFET is "on". b. Compute VSD in V when the MOSFET is "on". c. Compute the smallest possible motor resistance that will keep the MOSFET in the triode region in Ω. Note: In this problem, you may only submit numerical answers accurate to 0.02% or better. (i. e. If 4 is the correct answer, 3.9999 will be marked as correct, but 2+2 will be marked as incorrect.) a) ID : mA b) VSD : V c) RM : Ω
Derive Common-Mode Rejection Ratio (CMRR) from the given circuits: a) Ignore Lambda effects. M1 = M2. (ADM: 6 pts, ACM−DM: 6 pts)
Consider the amplifier shown below: a) Draw the small-signal equivalent circuit, assuming that the capacitors are short circuits for the signal. b) Assume that rd is infinite, and derive expressions for the voltage gain, input resistance, and output resistance. c) Find IDQ if R = 100 kΩ, Rf = 100 kΩ, RD = 3 kΩ, VDD = 20 V, Vto = 5 V, and K = 1 mA/V2. d) Determine gm at the Q point. e) Evaluate the expressions found in part (b) by using the values given in part (c). f) Find v0(t) if v(t) = 0.2 sin(2000πt) g) Is this amplifier inverting or noninverting?
The transistors have the following characteristics: nMOS: Vtn = 0.5 V, Kn′ = 400 μA/V2; pMOS: Vtp = −0.5 V, Kp′ = 100 μA/V2; Also assume the pMOSsQ3 and Q4 are identical and the nMOSsQ2 and Q5 are identical. VDD = 2.5 V and −VSS = −1 V. The required currents are ID = 100 μA and IREF = 50 μA. Also, the output voltage should be allowed to swing up to 2.3 V. (a) (i)Find the (W/L) ratio of all transistors and (ii) the resistor R. (25 points). (b) Show a clean and labeled small signal equivalent circuit with the values shown in the diagram. (10 points) (c) If all transistors have |λ| = 0.02 V−1, find the small signal gain vo/vin , Rin and Rout. . (10 points). (d) What is the minimum value of vO so that the transistor remains in saturation (5 points).
The following is a single stage amplifier circuit with an enhancement load. Assume that both transistors has the same W/L ratio and the threshold voltage VTn = 0.2×VDD. a) Provide an accurate sketch of the transfer function, vOUT versus vIN. (12 points) b) Provide an expression for the small signal mid-band gain of this amplifier. (8 points) Useful formulae: for n -channel MOSFET iDS = K[(vGS − VTH)vDS − 12 vDS2] triode region iDS = 12 K(vGS − VTH)2(1 + λvDS) saturation region
Consider an ideal n-channel MOSFET with a p+poly-Si gate, a width to length ratio of channel (W/L) = 2, SiO2 gate oxide thickness (Tox) = 10 nm, and body doping of NA = 5×1016 cm−3. Ignore poly-Si depletion in below questions. (20 points) (a) Calculate the threshold voltage (VTH). (b) Calculate the body effect coefficient (m). (c) Using the simplified bulk charge model, find the drain current (ID) at VGS = 3.5 V and VDS = 2 V. Assume an effective electron channel mobility (μn, eff) = 250 cm2/V⋅s. Use the values obtained from (a) and (b). If you haven't solved (a) and (b), use VTH = 1 V and m = 1.3. (d) Determine VTH with a body to source reverse bias VSB = 2 V. Assume a constant maximum depletion width (Wd,max) = 0.15 μm with a retrograde doping profile.
A simple form of a constant current circuit, known as a "beta multiplier," is shown in the figure. Neglect the Lambda effect. All devices are operating in saturation mode. μnCoxW/LN and μpCoxW/LP are both 8×10−3 A/V2. R1 = 500 Ω. VDD = 1 V. Vth, n = 0.30 V, Vth, p = −0.30 V What is the value of I1, and VGS1? The voltage value must be reasonable.
In the circuit of the figure: Data: VDD = 15 V R1 = 1 kΩ R2 = 1 kΩ R3 = 10 kΩ M1 and M2: k = 0.5 mA/V2 Vt = 3 VID = k(VGS − Vt)2 in saturation Questions: a) Calculate the voltage VGS in the transistor M1. Detail the used calculation procedure. b) Calculate the voltage VDS in M1. c) Justify the operating region in which the transistor M1 is working. d) Calculate the polarization point (ID, VDS) and the operating region of M2. Justify the answer.
The amplifier in the following circuit has VGS = 1.5 V, VDD = 15 V and RD = 3.5 kΩ. The parameters of the MOSFET are Vt = 1 V, K = 3.25 mA/V2. The nMOSFET is biased at its saturation region and can be characterized by the equation: iDS = K⋅(Vgs−Vt)2. Calculate DC bias point VDS. (The answer must be in unit 'V')
For a silicon nMOS capacitor with no fixed oxide charge or charge at the oxide-silicon interface, the substrate doping Na = 1017 cm−3 and an aluminum gate (ΦM = 4.1 V). Find the flatband voltage VFB.
The NMOS tree of a CMOS circuit is given below. (a) Find the logic function of this circuit at the out terminal. (b) Determine the PMOS tree for this circuit. Explain the configuration steps clearly.
A CG amplifier is required to match a signal source with Rsig = 100 Ω. At what current ID should the MOSFET be biased if it is operated at an overdrive voltage of 0.20 V? If the total resistance in the drain circuit is 2 kΩ, what overall voltage gain is realized?
A MOSFET is connected in the source-follower configuration and employed as the output stage of a cascade amplifier. It is required to provide an output resistance of 200 Ω. If the MOSFET has kn′ = 0.4 mA/V and is operated at Vov = 0.25 V, find the required W/L ratio. Also specify the dc bias current ID. If the amplifier load resistance varies over the range 1 kΩ to 10 kΩ, what is the range of Gv of the source follower?
Draw the small-signal model for the circuit shown below. Exclude ro and gmb (body effect). Assume that the body terminal of both transistors is grounded. Simplify as much as possible but be sure to include all relevant capacitances.
Problem 7 For the MOSFET amplifier circuit shown below, answer the following questions. Assume Vt = 2 V, kn′(W/L) = 0.5 mA/V2. (1) Perform DC analysis and find ID and VGS. (2) Perform ac analysis and find voltage gain (vo/vi). (3) Find the maximum value for vi to remain the MOSFET in saturation region.
A PMOS logic circuit is shown to the right. Consider the PMOS a SR model with |VTP| = 1 V, RON_p = 600 Ω. V5 = 3 V, R = 10 kΩ. Calculate Vo and static power consumption P in the circuit, when 1) Vin = 0 V and 2) when Vin = 3 V. Show your detailed process.
Question 2. (25 points) Assume the following current mirror. Q1 and Q2 are matched. Answer the following questions. A. (5 points) Assuming Q2 is in saturation, when does the output resistance of Q2, (ro2), affect the current Io? Explain your answer. B. (5 points) Assume both transistors are in saturation and operate at Vov = 0.5 V, Vt = 0.5 V, VDD = 5 V, kn′ = 800 μA/V2, (W/L)Q1 = (W/L)Q2 = 10, and |VA2| = |VA1|. What is VGS? C. (5 points) Given the assumptions in part B, what is IREF? (You can ignore channel-length modulation)
In the following CMOS inverter, the threshold voltages of the n- and p-channel transistors are VTn and −|VTp|, respectively: a) Draw the input to output voltage transfer characteristic (VTC) for this inverter. Express and label clearly all voltage levels on the VTC plot. (20 points) b) Indicate the noise margins NML and NMH on the VTC. c) Indicate the logic high and low output voltage levels VOH, VOL on the VTC. d) Indicate the logic high and low input voltage levels VIH, VIL on the VTC. e) Indicate clearly the mode of operation in each region of the VTC.
Question 2 The following parameters have been defined for the MOSFET amplifier circuit shown in Figure 2.1: VDD = 20 V, R1 = 2.2 MΩ, R2 = 1.8 MΩ, RD = 1.5 kΩ. (a) Given that the MOSFET has the parameters K = 0.475 mA/V2 and a turn-on voltage, Vto = 2.1 V, calculate the value of source resistance, Rs, needed to set a DC bias drain current of ID = 4 mA. [6 marks] (b) With Rs set at the value calculated in part (a), determine the value of the drain voltage, VD, and confirm whether or not the MOSFET is operating in the saturation region. [5 marks] (c) If the MOSFET has rd = 10 kΩ, complete the small-signal equivalent model for the amplifier circuit and calculate its input resistance, output resistance, open-circuit gain (i.e., with RL = ∞) and overall gain (when RL = 1 kΩ). [9 marks] Figure 2.1
Problem 5: Design a MOSFET amplifier with a gain of 50 using a transistor with the following specification 43 Points Ion = 10 A VT = 2 V kn′W/L = 3 mA/V2, The supply voltage that is available to us is 12 V. Please use a source resistor of 150 Kohm for temperature compensation and bypass it for audio signals. Once the design is complete, sketch the schematic of a suggested (do not need to design it here) output stage if this circuit will be used to drive speakers. The circuit should provide a clean signal with minimal distortion and the output stage should have a power efficiency greater than 50%.
For the given circuit assume λ = 0 along with the (W/L)s provided in the schematic (near the transistor). If Iref = 20 μA the values for I02 and I04 are given by (I02 / I04) Seleccione una: 50 μA / 200 μA 50 μA / 100 μA 100 μA / 200 μA 100 μA / 400 μA 400 μA / 800 μA
Consider the circuit below with a feedback resistance of RF = 82 KΩ and a drain resistance of RD = 5 KΩ. The small-signal model of the nMOS transistor is gm = 3 mS and ro = 10 KΩ. a. Find the input impedance RIN using the Miller approximation. b. Find the input impedance without using the Miller approximation. c. Find the output impedance Rout using the Miller approximation. d. Find the output impedance without using the Miller approximation.
Figure P4 shows output curves of an n-channel MOSFET with velocity saturation. A channel width (W) of the device is 1 μm. Answer below questions. Let's assume an ideal velocity saturation case. (15 points) (a) Using the curves at gate voltage (VGS) = 0.4, 0.5 and 0.6 V, explain the reason in detail that we can conclude the device is operating under the velocity saturation condition. (b) From these curves, find the gate oxide thickness (TOX) without calculating threshold voltage (VTH). (c) Calculate threshold voltage (VTH) without using the value of TOX from problem 4(b). (d) Calculate VTH using TOX from problem 4(b) and compare the result to the result from problem 4(c). *You MUST clearly describe the solving processes and the units, in detail. *Relative permittivity of SiO2(kSiO2) = 3.9, Si(kSi) = 11.7, and HfO2(κHfO2) = 25 *Permittivity of vacuum (ε0) = 8.85×10−14 F/cm Saturation velocity (vsat ) = 107 cm/sec Intrinsic carrier density (ni) = 1.5×1010 cm−3(@)T = 300 K) Elementary charge (q) = 1.6×10−19 C *Intrinsic carrier density of Si at 300 K:ni = 1.5×1010 cm−3
The ac equivalent circuit for an amplifier is shown in the given figure. Assume the capacitors have infinite value, RI = 10 kΩ, RG = 1.200 MΩ, RD = 4.100 kΩ, and R3 = 29 kΩ. The MOSFET Q-point is (2.400 mA, 8.50 V). Assume Kn = 7 mA/V2 and λ = 0. (Include a minus sign if necessary.) a. Draw the equivalent small signal model of the AC analysis b. Calculate the voltage gain for the amplifier if
What is the gm ratio between M5 and M6? Except W/L, device M5 and M6 have the same electrical properties. W/L ratios for P/NMOS are shown in the figure. Ignore Lambda effects. All transistors are working in Saturation mode.
In the circuit (W/L) = (2/3) for QREF and (W/L) = (4/5) for the other MOSFETs. The MOSFETs are identical in all other respects. If IREF = 30 μA, what is IA?
Assume the transistors have a threshold voltage of 0.5 V and 12 μnCoxWL = 4.3 mA/V2. The body is tied to ground. Specify whether the circuits below are PMOS or NMOS, and whether they are in cut-off, triode, or saturation mode of operation. Calculate IS, VGS, VDS, gm, ro (VA = 50 V), AC gain, and Rin. Type (NMOS or PMOS): Operation mode: VGS: VDS : IS: gm : r0 : AC Gain: Rin :
For the devices in the circuit of Fig. p4, |VT| = 0.5 V, λ = 0, μnCox = 400 μA/V2, L = 0.5 μm, and W = 0.5 μm. Find V2 and I2. How do these values change if Q3 and Q4 are made to have W = 5 μm? [15] Fig. p4
Required information Consider the transistor with threshold voltage, VTN = 0.75 V in the given figure: The drain current for the transistor in the given figure if λ = 0, Kn′ = 100 μA, and the W/L ratio is changed to 20/1 is μA.
P11.6. Suppose we have an NMOS transistor that has Vto = 1 V. What is the region of operation (linear, saturation, or cutoff) if a. vGS = 5 V and vDS = 10 V; b. vGS = 3 V and vDS = 1 V; c. vGS = 3 V and vDS = 6 V; d. vGS = 0 V and vDS = 5 V?
a) [2 marks] Determine the resistances, RI and R2, such that the bias current through the resistors is 1/10 of the drain current. For DC analysis, ignore channel length modulation, and assume that the MOSFET remains in saturation. b) [1 mark] Calculate the values of the small-signal parameters, gm and ro. c) [3 marks] Find the small-signal voltage gains, vx/vsig and vo/vsig. Vtp = −0.3 V, μpCox(W/L) = 1.2 mA/V2 and λ = −0.1 V−1. VSS = 3 V, I = 0.5 mA, Rsig = 2 kΩ, and RL = 10 kΩ.
What is the quiescent current in the class-AB stage in the figure given below if both transistors have IS = 3.300×10−15 A, VT = 0.025 V, and VGS = 1.300 V? The quiescent current in the given class-AB stage is μA.
a) Design the op amp given in the figure, and present the parameters (Vin, CM, Vbl, Vb2, (W/L)1−8, and ISS) of your design for the following requirements: Supply voltage = 3 V Maximum differential swing = 2.4 V Total power dissipation = 6 mW M1−M8 parameters μn = 350 cm2 /V/s μp = 100 cm2 /V/s Cox = 383.6 nF/cm2 VTN = 0.7 VVTP = −0.8 Vγ = 0 λ = 0