Questions tagged [multisim]
A SPICE simulation and schematic capture package distributed by National Instruments.
290
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Drawing a comparator op-amp in Multisim
I'm attempting to draw the following two circuits up in NI Multisim 10, to attempt simulation and confirm my calculations.
However, I'm not sure how to represent the Vin and Vout sources. Also, ...
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Simulation isn't working for high voltage amplifier
Been trying to simulate on multisim a circuit I saw about high voltage amplifier:
Schematic source seems to be:
EDN Design Ideas, 2004 - page 123 of 155 (displayed page number 110)
High-voltage ...
- 51
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3
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Why is series LC circuit not behaving as band pass filter?
I am trying to simulate LC circuit using external source that generates square wave of 503Hz of amplitude 2V as below:
Natural frequency of circuit above is 503Hz.So it must pass this much ...
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Summing RMS values proof [duplicate]
I have a simple circuit with two sources of different frequencies. I was tasked to get a voltage output across a component. I know for a fact that adding the derived voltage of both sources acting ...
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Problems with Wien Bridge oscillator circuit simulation in Mutisim
I am trying to build a Wien bridge oscillator that oscillates at 2.1kHz and that can be switched on by a transistor. The reason for me placing a transistor switch in the circuit is so that I can turn ...
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TTL NAND analog amplifier does not work in Multisim - why?
I have found in Dieter Nuhrmann's book an interesting approach to amplifier circuit and decided to test it.
Unfortunately the Multisim simulation does not work as expected. The signal is not ...
- 1,421
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Simulating Charged Capacitor
Is there any in built mechanism to simulate a charged capacitor in simulation software like Multisim or Proteus?
If not, is there any alternative method for simulation of partially charged Capacitors?...
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Simulating a magnetic field in Spice
I am trying to simulate a circuit that involves pickup coils in Spice. How would one simulate the magnetic fields that the pickup coils can sense? Additionally, how would one get a frequency response ...
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Can't get 5V 3A DC constant
Here's the circuit I am trying to build.
I want to get 5V 3A DC output but it's giving above 7V and 4A.
I have checked it in the multimeter attached in the diagram.
Can any one explain what's ...
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Series Parallel batteries
I am trying to simulate a series parallel battery design.
When I try to simulate, I am getting this error:
Voltage source loop found: V9, V1, V2, V10.
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How can I verify the max power theorem in a buffer opamp?
I was thinking since the buffer makes the output follow the input the power should be the same in a buffer opamp circuit and a resistive load.
There is the next circuit (the expected power was .5W, ...
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BJT current gain: Relation of SPICE parameter BF to beta
As far as I understand, the BJT (bipolar junction transistor) DC forward current gain in common emitter configuration is given by
It seems those symbols all used to describe the same thing (correct ...
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How to determine what kind of response this filter has
I have the next Sallen Key type filter
I have determined the transfer function and the coefficients of \$a_{0}\$ and \$a_{1̣̣}\$, based on
\$N(s)=\frac{Ka_{0}}{s^{n}+a_{n-1}s^{n-1}+....a_{1}s+a_{0}}\$...
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Where is the plain wire in NI Multisim
Could somebody please tell me where to find wire in the NI Multisim to connect logical gates to the VCC? I cannot find it.
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Multisim and choosing a FPGA Board
A couple years back in my Digital Electronics class we designed circuits in NI Multisim and then used Xilinx Impact to put it on a FPGA board via USB.
It has been a while since I dealt with that ...
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How to design a SPICE model from data sheet?
I am new to SPICE simulation and I am looking for spice model file of LTC 1065 data sheet can be found here here.
I searched a lot on Google but I could not find ...
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Problem with Wien's Bridge basic working and simulation in multisim
I am very new to the concept of Wien's bridge and am trying to make a basic circuit of it but didnt get the expected output (noise only).Tried to simulate on Multisim but got the same output.I have ...
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Equivalent resistance of circuit
I have a simple resistor circuit that i would like to know the equivalent resistance of(as seen from the multimeter terminals):
The image is from Multisim and the resistance is here measured using ...
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Is it possible to open two files simultaneously in Multisim?
It seems that Multisim provides useful feature of
File trees:
And design file tabs:
However, I was never able to find the way to use them. Is it possible to open different files at the same time for ...
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Low Pass Sallen-Key filter has weird response in bode plot
I have the following circuit in Multisim and am getting the Bode plot at the bottom. Could someone please explain to me what is happening?
The AD8651 is listed as having a 50MHz bandwidth. Why is it ...
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How do I simulate an audio amplifier in Multisim?
I'm new to Multisim and am using the 12.0 PowerPro version. I have designed the circuit in the question TDA2002 Audio Amplifier using Multisim:
The Multisim circuit may be found here. Instead of a ...
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Simulating noise signals in Multisim
I would like to simulate the effect of noise in a circuit built in Multisim so that I can make better component choices to improve my design. The main source of concern for me is that the circuit will ...
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5V power supply using 7805 with multiple outputs [closed]
I need to make a 5V power supply using LM7805 IC but it should have multiple outputs I'll be needing 6 outputs for my project.
Can anyone guide me how do I build a circuit on multisim for the same?
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Converting a circuit from Multisim into a PCB
I drew this metal detector circuit in Multisim. How can I make a PCB board from it?
Is there an option in Multisim to convert it to PCB or do I need another program?
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Inverting Op Amp: Why does current flowing into output seem to magically reappear at ground?
I'm trying to understand the flow of current through the inverting op-amp circuit. I've created a simulation:
The thing that is baffling me is: How come the values of PR1 (op-amp output) and PR2 (...
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Pre-amplifier for speaker
I am currently working on a school project which involves building an audio amplifier. Right now I am at the pre-amplifier stage and when i tried simulating it in multisim, the output seems to be ...
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Active clipper terrible performance
I need a clipper for a 10 kHz signal to protect an ADC from possible overvoltage. I'm using the usual active circuit (simulation is in multisim):
Unfortunately the result is very bad, the opamp is ...
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How to design over voltage protection Crowbar Circuit?
I'm designing a Crowbar over voltage protection circuit with following specifications,
Maximum input voltage - 30V
Maximum input current - 5A
Output voltage - 5V
Output current - 5A
So I have ...
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Is a battery a reasonable model for a forward biased diode? Why are the knee voltages different in the below Multisim schematics?
Here are two DC sweeps from Multisim.
One ranges from 0 to 15 mA and the other 0 to 50 uA. They are different.
What battery voltage should be used to model a silicon diode?
Ultimately, my question is: ...
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How to simulate LVT BiCMOS PSpice models?
I'd like to simulate the digital 74LVTxx chips with their analog characteristics. Packages like Multisim and OrCad only have the basic models (e.g. 74LS04N).
...
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Wien Bridge Oscillator in Multisim
I am trying to build a Wien Bridge Oscillator in Multisim that has a frequency of 500kHz. I went through all of the necessary calculations to choose values for R and C. When I build the circuit in ...
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Why does my SPICE simulation have a different lambda value from my model files lambda value?
I'm currently running a few labs here on my own since my university cannot do them in person and I have a SPICE model file in which the lambda value is set for a transistor. When I run a DC sweep on ...
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Band Pass Filter for musical note separation
I have a school project that i need to separate musical notes with filters at least i thought that i can do it with band pass filter, here are the results
These are the resistor and capacitor values ...
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1
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What component should I use to represent a solenoid valve in multisim
I'm trying to model a 12V 500 mA pilot assisted solenoid valve in NI Multisim, but it doesn't have any solenoid components that I see. I thought I could just model it with an inductor or relay, but I ...
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NE555 load resistor?
I'm using 555 timer in astable mode. I've used Multisim to generate it ant this is what I've got:
I'm little confised by the 100 ohms Rl resistor. Do I need it there ? If I do, why ? I've tried with ...
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Gain loss in two-stage direct-coupled amplifier
I am designing a direct-coupled two-stage amplifier with the following design constraints.
VCE swings of both BJTs should be the same
2nd stage current (IC2) should be between 10 or 20 times the 1st ...
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How to use phototransistor in Multisim?
I've multisim 14.2.
I not succeeded in make a phototransistor or photodiode to work.
I've tried a circuit like this
But no way to work.
Any clues? I don't know how to do it.
Thanks a lot.
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Digital Alarm Clock in Multisim. (Home Work/ Final)
I apologize for the schematic. I know it is not the prettiest to look at. My clock runs slow. I know this is because of my 555 timer. I was off somewhere in my calculations and ended up with a 70hz ...
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How to DC bias the output of a Wien Bridge oscillator so that it oscillates about 2V?
I was wondering what a practical method of biasing the output would be so that it osicllates around 2V? I tried connecting an DC voltage source in parallel to the positive terminal but alas the output ...
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1
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Active Bandpass Filter Design Issues
I am trying to design a bandpass filter that would have cutoff frequencies at 150Hz and 500Hz. The main purpose of this will be filtering notes played on a piano (or generated pure tones) that are ...
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Finding right component package in Multisim
I have started using Multisim.
I designed a 5V regulator and it works in simulation, now I want to export it to UtilBoard but I can not find the right package or footprint for my component as there ...
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How to determine LS, CS, RS, and CO of a piezo transducer for simulation?
I have a 24mm piezo transducer with the marking SSE2425TAL from overseas. There are no detailed specs nor graphs to get LS, CS, RS, and CO at various frequencies (but just 25 kHz is fine).
I'd like to ...
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Multisim : Wrong Output for 1 way traffic light using 555 timers
I made a curcuit using the given diagram in Multisim but my output is of the order Green->Yellow->Green->(Yellow and Red) . Pls tell what should I do to get the output of the order Green->...
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Multisim, Simulation Error
As the picture describes, the Vout is the division's result, but we have an error. Because my experience with MultiSim is not at a high level, why does this happen? Is this my fault ?
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How to log data in multisim?
I am running a simulation in Multisim. I am currently capturing data with the generic 4 channel oscilloscope component and manually saving the results to file after a short run. I would like to let ...
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Practical integrator using op-amp
I'm trying to simulate a practical integrator using NI Multisim 741 op-amp. But I dont quite understand a variation in my waveform.
I'm applying a 1 kHz, 5 V sinusoidal signal as input to the op-amp. ...
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LM7805 for stable 5V output
For a project I need to make a circuit to produce a stable 5V output. The input range is 5V to 15V.
Im using the LM7805 as it seems most logical, but when the input is less than 7V the output drops ...
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Unexpected behavior of the Sallen-Key second order filter
I met an unexpected behavior when I simulated under Multisim (National Instruments) the Sallen-Key circuit given on the image below.
The circuit is designed to receive a 1.8kHz modulated sin wave as ...
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Inverting op-amp unexpected voltage shift
I'm trying to create an op-amp circuit that attenuates a 5 V input signal down to a 1 VRMS Vout signal (1.414 V Vout).
I need to shift the output signal by 2.5 V so that it can be fed into a unipolar ...
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Multisim results not matching handwritten results
I was given a project with the following question:
I calculated the current going through inductor 2 in transformer 2 as 4 phase angle -30.
\$Vs = 1440 V RMS\$
\$V_1 = \frac{1}{3} * V_S = 480 V RMS\$
...
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