A dc sweep will apply multiple values to a voltage, or current, source. Orcad tutorial simulating the circuit parallel systems. Double click on the voltage source symbol and notice that in this vpulse source, the initial voltage level v1 is 0v. Pspice toolbar completely grayed out, unable to make new. The vpulse source has 7 parameters affecting the waveform. The purpose of this note is to show how such a dc voltmeter can be easily built in pspice.
Choose pspice run or click the run pspice toolbar button. These two spice simulation methods sweep a circuit over a defined voltage or. Add advanced markers on the schematic loadoutput to plot bode plot directly. Jun 12, 2018 thank you for watching the material on this channel and i hope the lectures are helping you make progress in your circuit designs. Orcad pspice probing issue no simulation data for marker. Pspice graph with db function and without db all about. When this occurs, the output voltage is related to the zener voltage through the rf1, rf2 divider by 44 footer pspice lab. To do this we go to pspice new simulation profile in the toolbar. Next place the db voltage marker on the out net, pspicemarkersadvanceddb magnitude of voltage.
The magnitude frequency response is often depicted in decibels db. Pspice displays the db magnitude 20log10 of the voltage at the marked nets. The tutorial starts under the assumption that the demo version of pspice is installed on your computer. Then run the simulation, pspice run, the simulation will run and the the probe window will open with the frequency response at the out net shown. Probe displays the db magnitude 20log10 of the voltage at the marked nets, out and mid, as shown. The yaxis can be any simple mathematical function of any of the voltages or currents in the circuit under simulation. Organized into 22 chapters, each with exercises at the end, it explains how to start capture and set up the project type and libraries.
Many common system behaviors produce simple shapes e. The actual plot will follow the asymptotic lines being 3 db below the first corner point i. An alternative to show the voltage in db and phase is to use markers on the schematics. Description how to get the bode plot of your circuit.
Orcad pspice tutorial bode plot of rc circuit new pspice. Also, probe has several builtin functions such as taking the magnitude of a voltage or current, finding its db equivalent or phase. Double click on the voltage source symbol and notice that in this. It would be pleasing to have pspice measure this voltage or any differential dc voltage for us. Hi all, as title says i would like to know how to display db vs frequency in orcad pspice. Analog design and simulation using orcad capture and pspice. What is the difference between the amplitude and the. This should be somthing like db vvoutvvin where vvin and vvout are the names of your input and output voltage signals. Figure 20 db magnitude curves for gain at mid and out. Use the p function to plot the phase response of your system. The following instructions will also work for a current source.
The plot should show the frequency response of the magnitude of the output voltage, with a linear voltage axis. The amplitude of a variable is the measure of how far, and in what direction, that variable differs from zero. Note that a phase shift of 90 degree is what we expect between the current and voltage signals across a capacitor. The program has a nice collection of circuit parts. Cadence pspice technology offers more than 33,000 models covering various types of devices that are included in the pspice software. Using the value of f 0 db 1 khz found above from the magnitude plot of figure 8, the openloop phase at f 0 db is.
Determine the frequency at which the amplitude of the output voltage v o is a maximum. In figure 39 the trace being shown if for what is called vc1. The control voltage at the c terminal is subtracted by a sawtooth waveform generated by a voltage source. Chapter 3 frequency response of basic bjt and mosfet. Instruction set for simulating power electronics using. In principle you can download the demo version from. Pspice is not case sensitive, so m and m is the same thing.
In the probe window, add the traces for the input voltage. Of course, we generally prefer use a bode plot to display the magnitude information. Schematics obey the passive sign convention shown in. Can you give formula to converting db into its equivalent magnitude and angle phase. On the schematic, click the enable bias voltage display button to see all the dc voltages in the circuit as shown below. A bode plot is a standard format for plotting frequency response of lti systems.
The op amp then adjusts the drive to q1 such that v is equal to the zener voltage vz. Then choose a db probe from the pspice menu item pspice markersadvanceddb magnitude of voltage, and place it on the node between the capacitor and resistor. Next place the db voltage marker on the out net, pspice markersadvanced db magnitude of voltage. A visual tutorial for schematics njit ece undergraduate. Download pspice for free and get all the cadence pspice models. I assumed you wanted a voltage source instead of a current source as youve drawn it, but your post isnt very clear. Now its time to ramp up the difficulty with dc sweep and ac sweep analysis. Analog design and simulation using orcad capture and pspice provides stepbystep instructions on how to use the cadenceorcad family of electronic design automation software for analog design. It rises to v2 of 1v with a delay time td of 0s, a rise time tr of nearly 1fs, and a fall.
For an op amp with a finite cmrr, a 0cm a 0d cmrr b. They can be accessed by option pspice from toolbar markers advanced db magnitude of voltage, phase magnitude of voltage and others. Look really close at the db graph and you will see that it is just slightly over 0db in the same area. Use the db function to plot the gain of your system in dbs. Pspice toolbar completely grayed out, unable to make new simulation profile. Then choose a db probe from the pspice menu item pspice markersadvanced db magnitude of voltage, and place it on the node between the capacitor and resistor. This is the place i get the frequency response traces. As discussed in class there are four types of dependent sources, two are voltage sources and two are current sources. Use pspice and ac analysis for a single point 60 hz to obtain the node voltages v1 and v2, and current in r3. For instance, suppose we wanted to make the voltage source above model. All db scale is doing is converting the output to db.
Orcad pspice how to get the bode plot of your circuit youtube. The frequency response is determined using the ac analysis feature of pspice. Learn to use orcad pspice to get the bode plot of your circuits. Not a pspice user so i cant comment there, but heres how its done in ltspice. Pspice does not care what units you use, it will automatically choose the appropriate unit. In between the two corner point the plot will approach the asymptotic line of constant value 60 db. Amplitude and magnitude, both these terms are similar with a minute difference. Bruce carter, in op amps for everyone third edition, 2009. It is a standard format, so using that format facilitates. Analog design and simulation using orcad capture and pspice provides stepbystep instructions on how to use the cadenceorcad family of electronic design automation software for analog design and simulation. How to get the gain in db against frequency curve for this. It is a standard format, so using that format facilitates communication between engineers. First, make the schematic, setting the voltage on the source to ac 1.
Perform an internet search using pspice voltage differential marker. Use pspice and probe to graph the magnitude of the output voltage v o as a function of frequency. V1 first voltage v2 second voltage td initial delay tr absolute rise time tf. This should be somthing like dbvvoutvvin where vvin and vvout are the names. Orcad is basically a schematic editor allowing you to draw circuit schematics. Then choose a db probe from the pspice menu item pspice markersadvanced db magnitude of voltage, and place it on the node. The four types of dependent sources are listed below in table 1 along with their abbreviation, pspice name and library. If you want a copy to install on your own windows machine, go. Transforming the voltage source to the current source and writing the node voltage equation results in. Pspice utilizes the implied 1 and 2 ends for it s handling of current directions and voltage polarities, for example, it represents current as entering a device from its 1 end and leaving its 2 end, and it represents a positive voltage at its 1 end with respect to its 2 end. An annoying problem in pspice is the inability to change some properties of the part.
The analysis of output filter for grid connected single phase. Pspice tutorial 10 frequency response of circuits this tutorial describes the use of pspice to determine the frequency response of a circuit. Marker on the out net, pspicemarkersadvanceddb magnitude of voltage. I ascended down the block then tried isolating the inputs making them floating and applied 5vdc to one of the l298 block inputs to see if i get 5v inside the block as well as outside, no dice. Use the ac analysis to sweep the source frequency linearly from 450hz to 500hz in steps of 0. Chapter 3 frequency response of basic bjt and mosfet amplifiers. Delete the voltage marker from the mid net if you added one for the previous simulation. Ac sweep capture pspice markers advanced db magnitude of voltage, phage of voltage.
Source controlled multiple controlling sources voltage source. How do i calculate the voltage drop across a resistor. Transforming the voltage source to the current source and writing the nodevoltage equation results in. The voltage is raised in the red region because that is what the circuit does. Thank you for watching the material on this channel and i hope the lectures are helping you make progress in your circuit designs. Dependent sources dependent source abbreviation pspice name library voltage controlled. Becoming familiar with this format is useful because. The voltage can be displayed in db by specifying vdbout in the add trace window type vdbout in the trace expression box. It is likely that the old url for this pspice tutorial will disappear on august 31, 2015. There are two ways to have the voltage expressed in decibels. Oct 01, 2011 learn to use orcad pspice to get the bode plot of your circuits. Pspice utilizes the implied 1 and 2 ends for it s handling of current directions and voltage polarities, for example, it represents current as entering a device from its 1 end and leaving its 2 end, and it.
After the simulation has successfully completed, results automatically display within the probe window. Magnitude, phase and transient response of a filter orcad. V1 first voltage v2 second voltage td initial delay tr absolute rise time tf absolute fall time pw pulse width per period to simulate a step response, we use a vpulse source set to v10v, v21v, td0, tr1ps, tf1ps, pw1s, and. Magnitude response to obtain the frequency response of the filter we choose ac sweep noise in the analysis type, logarithm as the ac sweep type and run the simulation from the start frequency of 0. This section describes how to use orcad capture to create the simple diode. Circuit with bias voltage display enabled on the schematic, click the enable bias voltage display button to toggle it off. View and download orcad pspice instruction manual online. Display measurement of dc differential voltage in pspice. The four types of dependent sources are listed below in table 1 along with. The output voltage of an op amp at dc can be expressed as v 3 a 0d v 2. Pspice provides an easy way to do this once the ac frequency response has been run. To display a bode plot of the output voltage, including phase. Spice is a powerful general purpose analog and mixedmode circuit simulator.
Print ac command tells pspice to report on the voltage magnitude and phase angle at node 3, and the current magnitude and phase angle for the current through resistor rm and the current magnitude and phase angle through capacitor cx. I ascended down the block then tried isolating the inputs making them floating and applied 5vdc. We added a second window to display the phase in addition to the magnitude of the output voltage. But the voltage probes with the no simulation data for marker warning remain grayed out. Ac command sets up the analysis for a single solution at 60 hz. In part 2 we showed you how to run a fundamental operating point analysis to simulate current and voltage at a single reference point. Magnitude response to obtain the frequency response of the filter we choose ac sweep noise in the analysis type, logarithm as the ac. Pspice engine through a simple example a diode recti.
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