1 / 12

EENG 2920: Circuit Design and Analysis Using PSpice Class 4: Transient Analysis (2)

EENG 2920: Circuit Design and Analysis Using PSpice Class 4: Transient Analysis (2). Oluwayomi B. Adamo Department of Electrical Engineering College of Engineering, University of North Texas. Switches.

osmond
Download Presentation

EENG 2920: Circuit Design and Analysis Using PSpice Class 4: Transient Analysis (2)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. EENG 2920: Circuit Design and Analysis Using PSpiceClass 4: Transient Analysis (2) Oluwayomi B. Adamo Department of Electrical Engineering College of Engineering, University of North Texas

  2. Switches • PSpice allows the simulation of a special kind of switches, whose resistance varies continuously depending on the voltage or current. • When the switch is on, the resistance is RON, and when it is off, the resistance is ROFF. Switch On state Off state EENG 2920, Class 4

  3. Voltage-Controlled Switch • The symbol for a voltage-controlled switch is S. The name of this switch must start with S, and the general form is: • S<name> N+ N- NC+ NC- SNAMEwhere N+ and N- are the two nodes of the switch. The current is assumed to flow from N+ through the switch to node N-. NC+ and NC- are the positive and negative nodes of the controlling voltage source. SNAME is the model name of the switch. • Model parameters for voltage-controlled switch (Table 4.8, page 113) • VON: control voltage for ON state, unit: V, default: 1. • VOFF: control voltage for OFF state, unit: V, default: 0. • RON: ON state resistance, unit: Ohms, default: 1. • ROFF: OFF state resistance, unit: Ohms, default: 1E6. • Note: RON and ROFF must be greater than zero and less than 1/GMIN. The default value for GMIN is 1E-12 mhos. The value of ROFF should be as high as possible and that of RON should be as low as possible as compared to other components in the circuit. • The voltage-controlled switch device from “breakout.olb” can be edited and new models can be defined in the same way as resistor. For example, • .MODEL Smod1 VSWITCH (RON=0.5 ROFF=10E6 VON=0.7 VOFF=0) EENG 2920, Class 4

  4. Current-Controlled Switch • The symbol for a current-controlled switch is W. The name of this switch must start with W, and the general form is: • W<name> N+ N- VN WNAMEwhere N+ and N- are the two nodes of the switch. The current is assumed to flow from N+ through the switch to node N-. VN is the voltage source through which the controlling current flows. WNAME is the model name of the switch. • Model parameters for voltage-controlled switch (Table 4.9, page 118) • ION: control current for ON state, unit: A, default: 1E-3. • IOFF: control current for OFF state, unit: A, default: 0. • RON: ON state resistance, unit: Ohms, default: 1. • ROFF: OFF state resistance, unit: Ohms, default: 1E6. • Note: The current through voltage source VN controls the switch. The voltage source VN must be an independent source, and it can have a zero or a finite value. Limitations on other parameters are similar to voltage-controlled switch. • The current-controlled switch device from “breakout.olb” can be edited and new models can be defined in the same way as resistor. For example, • .MODEL Wmod1 ISWITCH (RON=0.5 ROFF=10E6 ION=0.07 IOFF=0) EENG 2920, Class 4

  5. Time-Dependent Switches • Time dependent close switch: Sw_tClose • This switch is normally open; setting the closing time closes it. • Time dependent open switch: Sw_tOpen • This switch is normally closed; setting the closing time opens it. • From library: • The devices Sw_tClose and Sw_tOpen are from the library “eval.olb” in the lite version of Capture (the one you got with book) • The devices Sw_tClose and Sw_tOpen are from the library “ANL_MISC.olb” in the Capture CIS, the version in the EE Labs • Model parameters for time-dependent switches (Table 4.10, page 120) • TClose/TOpen: time at which switch begins to close/open. unit: s, default: 0. • ttran: time required to switch states from off state to on state (must be realistic, not 0), unit: s, default: 1us. • Rclosed: closed state resistance, unit: Ohms, default: 10mOhm. • Ropen: open state resistance (Ropen/Rclosed < 1E10), unit: Ohms, default: 1MEGOhm. EENG 2920, Class 4

  6. Example 4.7 • Draw circuit as shownin the figure. • Vs is VSIN from “source.olb” • Parameters for SMOD: • .MODEL SMOD VSWITCH ROFF=10E9 RON=5M VOFF=0 VON=25M • Run simulation to obtain the result • Analysis type is Time Domain (Transient) • Run to time: 1ms • Max step size: 5us Figure 4.7.1 EENG 2920, Class 4 Figure 4.7.2

  7. Example 4.8 • Draw circuits • S1 is the Sbreak from “breakout.olb” • Model for SMOD: • .model SMOD1 VSWITCH RON=0.01 ROFF=10E5 VON=0.1 VOFF=0 • Run Simulation • Transient Analysis • Run to time: 20ms • Max step size: 5us Figure 4.8.1 EENG 2920, Class 4 Figure 4.8.2

  8. Example 4.9 • Draw circuit • W1 is from “analog.olb” • Run simulation • Analysis type: Time Domain (Transient) • Run to time: 160us • Max step size: 1us Figure 4.9.1 EENG 2920, Class 4 Figure 4.9.2

  9. Example 4.10 • Draw circuit • Sw_tClose is from “eval.olb” in theLite version of Capture. • Sw_tClose is from “ANL_MISC.olb”in the Capture CIS version (the version in the EE Labs). • Run simulation • Run to time: 160us • Max step size: 1us Figure 4.10.1 EENG 2920, Class 4 Figure 4.10.2

  10. Example 4.11 • Draw circuit • Sw_tOpen is from “eval.olb” in theLite version of Capture. • Sw_tOpen is from “ANL_MISC.olb”in the Capture CIS version (the version in the EE Labs). • Run simulation • Run to time: 100us • Max step size: 1us Figure 4.11.1 EENG 2920, Class 4 Figure 4.11.1

  11. Problem 4.22 (page 129) • Please note that the following changes have been made to the original problem • The control voltage of the voltage controlled switch S1 is Vc, i.e., the voltage across the capacitor. • Simulate the circuit and obtain the following result for the voltage across the capacitor C, i.e., Vc. • You need to include your final circuitschematics in your assignment report. (Your final circuit schematics) Figure P4.22.1 EENG 2920, Class 4 Figure P4.22.2

  12. Assignment 4 • Repeat and reproduce the results for Examples 4.7, 4.8, 4.9, 4.10, and 4.11, and Problem 4.22 on page 129 in the book. • Reproduce the figures on the previous slides and explain the functionality and the behavior of each circuit: • Figures 4.7.1, 4.7.2 • Figures 4.8.1, 4.8.2 • Figures 4.9.1, 4.9.2 • Figures 4.10.1, 4.10.2 • Figures 4.11.1, 4.11.2 • Figures P4.22.1, P4.22.2 • Assignment is due next week before class. • Compile all your results in a report and turn in the print-out of the document. See Class 1 notes for the report format. EENG 2920, Class 4

More Related