1. Overview This README.TXT file discusses some basic aspects of the Electronics Workbench and MultiSim circuit files accompanying "Electronic Devices", 6th Edition and "Electronic Devices: Electron Flow Version", 4th Edition, by Thomas Floyd. For simplicity, the titles of these textbooks will be abbreviated to "ED6" and "ED:EFV4" respectively, "Electronics Workbench" will be abbreviated "EWB", and "MultiSim" will abbreviated "MSIM" for the remainder of this file. This file intended for both the student and instructor, and is concerned primarily with explaining the organization and installation of the EWB circuit files. 2. Circuit Files 2.1. File Organization The circuit files are organized into two main groups. The first group consists of all files associated with EWB, and the second group of all files associated with MSIM. Within each group of files are the raw, or basic, circuit files referenced by the FAC textbook and the password-protected compressed solution files. The basic files are provided as a starting point for the student in completing the various exercises and problems. The solution circuits for these exercises and problems demonstrate diagnostic measurements of hidden faults and are intended for use by the instructor only. The passwords for both decompressing the solution files and for showing the hidden faults in EWB or MSIM are contained in the Instructor's Resource Manual, or IRM. 2.2 File and Folder Structure The basic file and folder structure for the CD-ROM is as shown: /ED6 - | README.TXT /EWB 5 - | /CHAPTER 01 - | /EXAMPLES /PROBLEMS /TROUBLESHOOTING EXERCISES /TROUBLESHOOTING PROBLEMS /CHAPTER 02 - | /EXAMPLES /PROBLEMS /TROUBLESHOOTING EXERCISES /TROUBLESHOOTING PROBLEMS ... /CHAPTER 18 - | /EXAMPLES /PROBLEMS /TROUBLESHOOTING EXERCISES /TROUBLESHOOTING PROBLEMS /SOLUTION - | SOLUTION.EXE | /MULTISIM 6 - | /CHAPTER 01 - | /EXAMPLES /PROBLEMS /TROUBLESHOOTING EXERCISES /TROUBLESHOOTING PROBLEMS /CHAPTER 02 - | /EXAMPLES /PROBLEMS /TROUBLESHOOTING EXERCISES /TROUBLESHOOTING PROBLEMS ... /CHAPTER 18 - | /EXAMPLES /PROBLEMS /TROUBLESHOOTING EXERCISES /TROUBLESHOOTING PROBLEMS /SOLUTION - | SOLUTION.EXE All circuits for Chapter 1 are contained in one of the subfolders of CHAPTER 01, those for Chapter 4 in one of the subfolders of CHAPTER 04, and so forth. All the circuit files corresponding to examples in the ED6 and ED:EFV4 textbooks are contained in the EXAMPLES subfolder, the circuit files corresponding to figures from the end of chapter problems in the PROBLEMS subfolder, the circuit files corresponding to the ED6 and ED:EFV4 troubleshooting section in the TROUBLESHOOTING EXERCISES subfolder, and the circuit files corresponding to the end of chapter troubleshooting problems in the TROUBLESHOOTING PROBLEMS subfolder. Note that not all chapters have a folder, as not all ED6 and ED:EFV4 chapters have related circuit files, and that some subfolders for a chapter may have contain no circuit files. The SOLUTION folder initially contains only the SOLUTION.EXE file. The various chapter solution subfolders are contained in the password-protected SOLUTION.EXE file and cannot be accessed until they have been extracted. The password needed to extract these files from the SOLUTION.ZIP file is given in the Instructor's Resource Manual, or IRM. SOLUTION.EXE is a standard 32-bit ZIP self-extracting compressed file and can be unzipped automatically or using PKZIP, WinZIP, or a number of other decompression utilities. 2.2. Circuit Filenames The EWB circuit files fall into one of two categories, and are named based upon the specfic chapter and example from which they come in the FAC text. The general filenames are Exx-yy.EWB or Exx-yy.MSM for example circuit files, Fxx-yy.EWB or Fxx-yy.MSM for problem circuit files, TSExx-yy.EWB or TSExx-yy.MSM for troubleshooting exercise circuit files, and TSPxx-yy.EWB or TSPxx-yy.MSM for troubleshooting problem circuit files. The value "xx" always refers to the chapter, while "yy" refers either to to the example number, figure number, or problem number corresponding to the circuit file. Thus E13-10.EWB would refer to the EWB file corresponding to Example 13-10 in the ED6 and ED:EFV4 texts, while TSP02-56.MSM would refer to an MSIM file corresponding to troubleshooting problem 56 at the end of Chapter 2. In some cases a circuit file will have a letter (such as a, b, etc.) at the end of the filename. This is because some examples or problems have multiple parts. Circuit file F15-36B.EWB, for example, would be an EWB circuit file corresonding to Figure 13-56b in the ED6 and ED:EFV4 texts. 3. Circuit Installation The simplest means of installing the circuits on the user's PC is to copy the EWB or MSIM subfolder (and all its associated subfolders) from the CD-ROM to the desired hard drive using Windows Explorer as follows: 1) Open Windows Explorer using Start->Programs->Windows Explorer. 2) Expand the contents of the CD-ROM drive by left clicking on the "+" sign to the left of the CD-ROM drive icon. 3) Expand the contents of the FAC folder by left clicking on the "+" sign to the left of the FAC folder icon. 4) Select the EWB 5 or MULTISIM 6 folder by right clicking on it. This will open the options box. 5) Left click on the "Copy" option. 6) Select the target drive by right clicking on its icon in Windows Explorer. This will again open the options box, but this time there will be a "Paste" option. 7) Left click the "Paste" option. Windows will then proceed to copy the circuit folder and all its subfolders and files to the target drive. If the user wishes the entire ED6 folder can be copied from the CD, but very few users will be using both EWB and MultiSim. 4. Simulation Anomalies From time to time the user will simulate a circuit file and find that the behavior deviates somewhat from what they might expect. This is because simulators work with models of circuits which attempt to predict how an actual circuit might react to specific conditions. How well the simulation fits the behavior of real-world circuits depends both upon how accurate the circuit model is, and how well the simulation engine works. In the ED6 and ED:EFV4 circuits, there are some known issues with simulations using ideal components models of which the user should be aware. 4.1. Op-Amps In the case of real op amps the output voltage swing is limited by the voltage supplies which power it, referred to as the supply rails. It should be obvious that the output of an op amp cannot exceed the supply rails, although some real-world op-amps (called rail-to-rail output op amps) can come very close to reaching these voltages. In EWB the output voltage swing of an ideal op amp model can be set by editing the component properties of the model. In MultiSim the ideal op amp model has no such limitations, presumably because the op amp is intended to be run in a closed loop mode that inherently limits the output gain. When the ideal op amp model is run open loop (without negative or other limiting feedback. possibly due to a circuit fault) the output voltage is essentially infinite. Consequently, an oscilloscope or AC voltmeter reading can measure output voltages of kilovolts or even teravolts. In these cases it is simpler to consider that the output is "railed" as the output has clearly exceeded any realistic supply. In some cases where open-loop operation is deliberate, such as comparator functions, ideal op amps have been replaced with a real-world model to avoid simulation problems. 4.2. Oscillators On paper an ideal osicllator will do nothing, as typically the initial conditions will keep it in a steady-state zero-voltage condition. In EWB and MSIM this is also the case, so that the output of the oscillator will typically remain steady. The imbalances and noise that generally start oscillation in the real world are not present in the simulator, so that some means of initiating osicllation must be incorporated. In oscillator circuits which are not capable of self-starting a switch to force the circuit out of steady state has been included. Usually toggling the switch from one state to another and back again will initiate oscillation in a non-faulted circuit. In self-starting oscillator circuits, such as the JFET-controlled Wien-Bridge oscillator circuit, some tweaking must be done to find the optimal oscillation setting. This is not unlike what must be done in the real world, but the major exception is that the simulation time is much slower than realtime. When a potentiometer is adjusted, for example, the user must wait several realtime seconds to make sure that the simulation program has had time to process the change before making another adjustment. As the user slowly adjusts the potentiometer they should be able to see when the circuit is approaching instability from the circuit response on the oscillator. Once oscillation begins, the waveform will typically not be an optimal sine wave as conditions that sustain oscillation are not the same as those that will initiate oscillation. Further adjustment of the potentiometer will allow the user to obtain a more ideal waveform. 4.3. Transistors In some exercises it may be necessary to change the beta of a bipolar junction transistor. The procedure to do so differs for EWB and MultiSim. In EWB the procedure is as follows: 1) Double-click the transistor to open the Transistor Properties box 2) Click the "Edit" button to open the transistor model box 3) Select Sheet 1 tab 4) Enter the desired beta value in the "Forward current gain coefficient (Bf)" box 5) Click the "OK" button to close the transistor model box 6) Click the "OK" button to close the Transistor Properties box In MultiSim the procedure will differ depending upon the software version. Refer to your user's manual for details on how to edit the model for your version of MultiSim. 4.4. Instrument Loading The user may note that there may be minor differences in calculated vs. measured values for some circuits. This is typically due to circuit loading produced by the measurement devices used in the program (much as in the real world). In cases where extremely high circuit impedances (>1 megohm) exist the default instrument impedances have been adjusted, but in some FET circuits the loading effects cannot be completely eliminated. 5. Missing Circuit Files Due to difficulties that EWB or MSIM has with simulating some circuits, there are some files that will be available only for EWB or MSIM. Circuits that are exclusive to EWB include F13-60.EWB and E16-04.EWB. Circuits exclusive to MSIM include TSE13-06. Should the ED6 or ED:EFV4 text refer to a circuit file that does not exist in the folder for your application, it is most likely because the circuit could not be properly simulated in your application. 6. Tests The circuits on this CD-ROM were built and tested under Windows 98 using a 233-MHz Pentium MMX processor and 64 MB of RAM. The EWB and MSIM applications using these circuits are, as best as could be determined, stable and all circuit results reproducible under these conditions. There could be some minor variations in some readings (due to such factors as instrument resolution chosen, for example) but the results from each program should generally be in accord with each other and the expected values.