Help with Circuit to Invert Graph

  • Thread starter Thread starter sheheryarnoor
  • Start date Start date
  • Tags Tags
    Circuit
Click For Summary

Discussion Overview

The discussion revolves around creating a circuit to invert a graph, specifically focusing on the design and functionality of filters, such as low-pass and high-pass filters, in the context of electronics. Participants seek assistance in circuit design and simulation to achieve a desired output graph for a project.

Discussion Character

  • Exploratory
  • Technical explanation
  • Homework-related
  • Debate/contested

Main Points Raised

  • Some participants identify the circuit as a low-pass filter and suggest that to invert the frequency response, a high-pass filter may be needed.
  • One participant mentions that the phase response should be plotted to confirm whether the circuit is inverting, as the magnitude will always be positive.
  • There are requests for video tutorials and circuit diagrams to assist in understanding the circuit design.
  • Participants discuss the need to connect components correctly, including the orientation of voltage inputs and the configuration of op-amps.
  • Some participants propose combining low-pass and high-pass filters to achieve a specific bandpass response.
  • There are clarifications about circuit components, such as the ground symbol and the role of resistors and capacitors in the circuit.
  • One participant expresses frustration over not being able to replicate a desired output graph and seeks further assistance.
  • Another participant emphasizes the importance of using a high impedance load for the output.
  • Some participants share their own circuit designs and results, while others request specific guidance on their attempts.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correct circuit design or the best approach to achieve the desired graph. Multiple competing views and suggestions remain throughout the discussion.

Contextual Notes

Limitations include varying levels of understanding among participants regarding electronics, leading to potential miscommunication about circuit components and configurations. Some participants express a lack of familiarity with the subject matter, which may affect their ability to follow technical discussions.

Who May Find This Useful

This discussion may be useful for individuals interested in electronics, particularly those working on circuit design and simulation for projects involving filters and signal processing.

sheheryarnoor
Messages
21
Reaction score
0
Hi everyone i got project from someone

Here is the Project
Code: 
www.stanford.edu/class/ee122/Spice_Decks/pspicedemo.pdf

And i did the same what the pdf file tells

Here yall can see the video which i made

Code: 
[URL]http://rapidshare.com/files/390247187/CaptureWiz005.wmv
[/URL]

Or

Code: 
http://www.youtube.com/watch?v=4G82E2uDP2A

But rapidhsare one's quality is good


Circuit Pic
qnwryx.png



kcb040.png



The graph which i want to invert
1jx734.png


Can someone help me with inverting the graph?
What should i add in the circuit to invert the graph?
 
Last edited by a moderator:
Engineering news on Phys.org
Welcome to PF.

The circuit you have is called a http://en.wikipedia.org/wiki/Low-pass_filter" .
 
Last edited by a moderator:
dlgoff said:
Welcome to PF.

The circuit you have is called a Low-pass filter. If you want to invert your frequency response, you'll need a High-pass filter.
I think he's probably referring to inverting the amplitude, since it's an "inverting" amplifier topology.

To sheheryarnoor: Just plot the phase response and you'll find it's already "inverted" (as in 180 degrees phase shift in most of the pass band). What you have plotted there is a frequency response "magnitude". The magnitude will always be positive, you need to plot the phase to confirm whether it's "inverting" or not.
 
i made a circuit like this
2lvfnu8.png

But it gives me error.Isn't it same like high pass filter?i think it is but it is still giving me error
Can anyone make a video tutorial for me please
I need it for my friend he is in the hospital:(
 
This is an inverting amp with a gain of A=R2/R1. i.e. Vout=AVin
 
can anyone of u make a video tutorial of it for me?
or just draw a circuit even in Paint so i can know how the circuit will look like and what components there will be
Please i want to help my friend he is in the hospital
 
You need to connect the positive side of Vin to C1 and the negative input to ground -- right now you've got the negative side of Vin connected to C1 and an open circuit on the positive side. And also remove the voltage source on the output, and put your probe here.
 
i removed voltage source and connected as u said
n654pg.png


But the graph shows like this then

24c9j0w.png
 
When I said "the positive side" I meant the terminal that has a "+" sign next to it. The negative side has a "-" sign next to it. I'm not sure what you're trying to do anymore, but in your last attached picture (which I guess is supposed to be an "integrator"):

1) Connect the positive output of Vin (marked with a + sign) to the 1k resistor and the negative side to ground.

2) Connect the negative input of the opamp to the node where the resistors and capacitor meet, and the positive input of the opamp to ground.If your input signal is a square pulse train, what do you expect to get on the output?
 
  • #10
98yk5z.jpg


30w72hd.png


See the red lines i want graph like those red lines the red lines have been sketched in Paint to give me a clue that what graph will look like
Can u make like these?
Actually i am not a student of Electronics i am doing it for my friend he is in the hospital so i want to help him
Please help me to help him
 
Last edited:
  • #11
dlgoff said:
This is an inverting amp with a gain of A=R2/R1. i.e. Vout=AVin

Oops. Actually it is a high pass filter. I didn't see the capacitor at first. Sorry. The corner frequency = 1/2πR1C1 with a bandpass gain of R2/R1.
 
  • #12
lol as i told u am not a student of electronics just helping my friend
So i don't know what are u talking abt?:p
Can u make a graph like the red line?
 
  • #13
You can combine low pass and high pass filters to get passbands like that one.

[PLAIN]http://dl.dropbox.com/u/4222062/low%20pass%20high%20pass.PNG

Here R2 and C1 form a low pass filter to produce the slope from 10 KHz upwards and
C2 and R1 form a high pass filter to produce the slope from 1 KHz downwards.
 
Last edited by a moderator:
  • #14
what is this triangle thing which u have used?
GND Analog?or what?
 
  • #15
"vk6kro" Can u make a video of it?I tried to make a circuit like u have shown but mine graph was change it wasn't like urs
So i wish u make a video of it
 
  • #16
The triangle is a ground symbol.

Not sure what sort of video you mean. Why would you do that?

Are you plotting with LT Spice 4?
 
  • #17
"My friend's in hospital and the only thing that will cure him is a video of the simulation of a band-pass filter"

Man you've got to give this guy the award for most creative excuse of why someone else should do my homework/assignment for me. :smile:
 
  • #18
Hopefully his friend will have a speedy recovery and be able to do his own homework. :)

I'm sure we all wish him well.
 
  • #19
i mean get a screen recorder and when u make a circuit record it and then upload it to utube so i can see what did u do and what did i do wrong
 
  • #20
i mean make a circuit and graph like u have showed in ur pics
While making them make a video of it
Record ur screen by screen recorder so i can know what did i do wrong?
Upload it to youtube or rapidshare then
Can u do it please
 
  • #21
sheheryarnoor said:
i mean get a screen recorder and when u make a circuit record it and then upload it to utube so i can see what did u do and what did i do wrong

That isn't going to happen.

When your friend gets out of hospital, you can give him that circuit and he can do a simulation of it.

Note that the output should go to a high impedance load such as the input of an opamp connected as a unity gain buffer.
 
  • #22
Why man:-s
Why can't u do that?
 
  • #23
Vk6kro thanks bro i did it
Thank u so much i made a circuit like u have shown in the pic
I tried to make a graph like this but mine don't show like this
Can u make a circuit which can have graph like this on Vout

w70pdf.jpg
 
  • #24
Could you show the circuit you entered into the simulator?
 
  • #25
which one?
The one u made like it?
Or the one which i made wrong?
if u are talking abt the 2nd one then can't lol coz i saved and deleted the files coz it was wrong
 
  • #26
I already have a copy of my circuit. To work out what you are doing, I need a copy of your version of it.

Try entering just the signal source and the first 100 K resistor R2 and C1. Then try entering the rest of the circuit but without the 270 pF capacitor.
You should get results like this:

[PLAIN]http://dl.dropbox.com/u/4222062/low%20pass%20high%20pass%203.PNG

Can you see that the combination of these outputs will give the bandpass shape I got before?
 
Last edited by a moderator:
  • #27
Thankss 4 keep helping me but the one u made isn't what i need ur one look diff than the graph which i showed
i have mostly done it
Thanks again
 
  • #28
Anyone know how to make a circuit which can have graph like this on Vout
6i87fb.png
 
  • #29
Yes, have a look at the first circuit in post #26.

That one peaks at 50 volts because the supply is 100 volts. You would need a supply of 4 volts peak.
R2 isn't necessary and you would get the same shaped graph without it, but twice as much output.

Those graphs were drawn to let you find out what you were doing wrong with the simulator.

How is your friend in hospital?
 
Last edited:
  • #30
He is on medicines thanks for asking
Can u draw a circuit actually i m having exam
i am a student of computer science and i am into 3d designing so i don't know about electronics much
Draw a circuit for me and i will try to make a circuit like and will make a video if i do something wrong u will see it in the video
O.K
SO u can guide me
Can u please?
 

Similar threads

Op-amp compensation of cascade fudges audio signal oddly
  • · Replies 3 ·
Replies
3
Views
2K
Engineering Why is the voltage source high potential into node 1 at -12 V in this op amp problem?
  • · Replies 15 ·
Replies
15
Views
3K
Solving Power Delivery Issues in a 5V Series Circuit with a 1.5V Rated Relay
  • · Replies 12 ·
Replies
12
Views
3K
Debouncing rotary encoder circuits
  • · Replies 5 ·
Replies
5
Views
5K
Making a Simple Circuit with MOC3041 Optoisolator and BTA24 Triac
  • · Replies 4 ·
Replies
4
Views
7K
Can a DC to AC Inverter Circuit Be Simulated Using Multisim Software?
  • · Replies 2 ·
Replies
2
Views
15K
Increasing the Battery Life of an LED Circuit
  • · Replies 26 ·
Replies
26
Views
5K
Help analysing this circuit - how does it act like a low pass filter?
  • · Replies 6 ·
Replies
6
Views
3K
Understanding Frequency in Pulse Tone Oscillators
  • · Replies 4 ·
Replies
4
Views
2K
Two networks described by v-i graph: Find voltages when interconnected
  • · Replies 1 ·
Replies
1
Views
2K