TRƯỜNG ĐẠI HỌC SƯ PHẠM KỸ THUẬT TP. HỒ CHÍ MINH Mô phỏng mạch và hệ thống MultiSim – Fundamentals Circuit simulation Cuong Q. Ngo 1. Introduction • A simulation in Multisim runs in one of two simulation modes: – Interactive Simulation Mode – Analysis Simulation Mode 2 1. Introduction • Interactive Simulation Mode – This mode is used whenever you click the Run button. – It performs a time-domain simulation (transient analysis) until you press the Stop button. – Data is displayed by the instruments and by the indicator components. 3 1. Introduction • Analysis Simulation Mode – This mode is used whenever you press the Simulate button. – Allows you to set up a customized analysis and view the results in the Multisim Grapher during and after the simulation. 4 1. Introduction • Simulation Methods – Analogue simulation – Digital simulation – Mixed-mode simulation 5 1. Introduction • Analogue simulation – The goal of analog simulation is to calculate a circuit's voltages and currents in accordance with Kirchoff's Current Law(KCL) and Kirchoff's Voltage Law (KVL). 6 1. Introduction • Digital simulation – To determine the nodal values of a network of elements which are characterized by a discrete state system. – Each digital element simply reads the digital signal on its input, performs some Boolean logic operation, optionally saves the state, and places a calculated signal on its output after a specified delay. 7 1. Introduction • Mixed-mode simulation – Mixed-mode simulation refers to the simulation of circuits in which analog and digital elements are interconnected. 8 1. Introduction • Analyses Multisim offers you many analyses, all of which use simulation to generate the data for the analysis you want to perform. 9 2. DC Operating Point Analysis • Determines the DC operating point of a circuit. • The results of DC analysis are usually intermediate values for further analysis. • Assumptions: – AC sources are zeroed out – Capacitors are open – Inductors are shorted – Digital components are treated as a large resistor to ground. 10 [...]... 2.2kΩ Q1 2SC1815 R4 10kΩ R3 220Ω C3 100µF 11 3 DC Sweep Analysis • As this analysis is performed in Multisim, the following procedure is performed: – The DC operating point is calculated – The value from the source is incremented and another DC operating point is calculated • This procedure allows you to simulate the circuit many times, sweeping the DC values within a pre-determined range 12 3 DC Sweep... Applied to an analog circuit, small-signal 15 4 AC Analysis (cont’d) • Nêu các bước để phân tích đáp ứng tần số cho mạch: 16 4 AC Analysis (cont’d) 17 4 AC Analysis (cont’d) 18 5 Transient Analysis • Multisim computes the circuit’s response as a function of time • Each input cycle is divided into intervals, and a DC analysis is performed for each time point in the cycle 19 5 Transient Analysis (cont’d)... -12V U2 3 6 2 4 VEE R2 10kΩ 741 R4 1 R3 741 VEE -12V 22kΩ R5 10kΩ R6 22kΩ 26 MORE ANALYSES 27 Parameter Sweep Analysis • Verify the operation of a circuit by simulation across a range of values for a component parameter • The effect is the same as simulating this circuit several times, once for each value • Three types of analysis that can be performed on the circuit while the component is manipulated: . thống MultiSim – Fundamentals Circuit simulation Cuong Q. Ngo 1. Introduction • A simulation in Multisim runs in one of two simulation modes: – Interactive Simulation Mode – Analysis Simulation. simulation. 4 1. Introduction • Simulation Methods – Analogue simulation – Digital simulation – Mixed-mode simulation 5 1. Introduction • Analogue simulation – The goal of analog simulation. Mixed-mode simulation – Mixed-mode simulation refers to the simulation of circuits in which analog and digital elements are interconnected. 8 1. Introduction • Analyses Multisim offers