![]() Source folower and Common-Source Amplifiers You will want to show simulation (Scilab/Xcos) results to illustrate your approach. How will you compute the output resistance, Rout, and transconductance, Gm, from experimental measurements. Output resistance, and voltage gain of a transconductance amplifier.Įxplain how you would measure the voltage gain for a transconductance amplifier if you were given Quantitatively show the relationship between transconductance, You will find this expression helpful for some of the experimental curve fits. If V1 You should neglect the effect of Early voltage (channel length) for this calculation. Derive the currents I1 and I2 as a function of V1, V2, and Ib, assuming all transistors operate below threshold.2 is operating with subthreshold currents, is that sufficient to assume that all the MOSFETs are in subthreshold? Why or Why not? What is the minimum drain-to-source voltage required for this biasing current source transistor if it is operating with subthreshold currents? If we assume that the biasing current source transistor in Fig.You should assume that all MOSFET transistors will be operating in subthreshold throughout this homework set. One should go through these questions before attempting the data problems below. Make a single plot of the output voltage versus the input voltage for this amplifier.Īnd compare it to typical values of Early voltage (sigma), kappa, and UT įor example, compare to your recently extracted value for "sigma".įigure 2: Differential Transistor Pair circuit.Notice where the data makes a sharp transition, and relate this value to measured parameters and bias voltages. Obtain a dense sweep of the transfer curve between the amplifier (gate) input and the amplifier output (drain). The pFET current source transitor was biased to roughly 10nA. If you needed a very high gain amplifier of this type, how would your design your transistors to achieve this very large gain?.How does this modify the amplifier gain from the ideal current source model for the same bias current? ground) applied to Vb (pin (30)) sets the bias current. 1(b,c) where we use a MOSFET as the current source. A typical implementation of this amplifier is shown in Fig.How does this gain depend upon bias current in subthreshold? Qualitatively (or quantitatively) explain how the gain changes for above threshold current levels. You should solve for voltage gain without drawing a small-signal circuit,īut feel free to do so if you wish. What is the voltage gain from input to output? 1a, a transistor biased with a current source. 1(b,c).īefore jumping into the experimental data, first do some initial analysis assuming that these transistors are in subthreshold. The schematic for the nFET high-gain amplifier is shown in Fig. To help your understanding, consider the following questions: This derivation can be done effectively by inspectionĪlso important to show your high-level simulink files for each experiment performed. I do not need a detailed derivation in the presentation, We want to derive from the large signal equations the transfer function in the "gain" region, Like a source follower circuit, high-gain amplifier, and OTA circuit. Make sure you understand what the transfer function should look like for basic transistor amplifiers, With the model you extracted for the last project. Simulation will use the circuit simulator in Xcos / Scilab (transistor level) The measured data will all be possible using the remote system,Īlthough you are welcome to use a physical board if you prefer. This project will look at measured results from the MOSFET transistor circuits, Lecture 15 Boards (Follower-Integrator + Half Circuits ).Lecture 14 Boards (OTA Transconductance, Output Resistance, Gain).Lecture 13 Boards (Small Signal + Source Degeneration).Lecture 12 Boards (Small Signal Model Discussions).Lecture 11 Boards (Transient Behavior leading to Small Signal Models). ![]() Lecture 10 Boards (More Cascodes, Capacitors, Beginning of Transient Behavior).Lecture 9 Boards (Source Follower Transfer Function, Differential Pair, Cascode):.Lecture 8 Boards (Transfer Function of Common-Source Amplifier):.Lecture 7 Boards (Introduction to Circuits from Devices):.Chapter 9 Material : Follower-Integrator Circuit.Chapter 6 Material : Cool Circuit Techniques.Chapter 5 Material : OTA Circuit basics, Differential Transistor Pairs.Transconductance Amplifiers / Basics of FG Circuits.Basic MOSFET Circuits: Common-Source, Common-Gate, Source Follower, Differential Pairs.MOSFET as an approximate current source.Basic Transistor Circuits Basic Transistor Circuits Topics
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |