Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Hi all... How to superimpose 2 wave forms? Please Help me

Status
Not open for further replies.

Senthilkumar_rjpm

Full Member level 2
Joined
Jul 21, 2009
Messages
123
Helped
15
Reputation
30
Reaction score
15
Trophy points
1,298
Location
chennai
Activity points
2,039
Hi all...
some days before, For 1 of my project i needed wave form like this... (Below)



I can easily generate this wave form using this circuit (IC 4052) below...




And Now the same type of project i need this type of wave form... (below)



Now i didn't get any idea about to generate this wave form combination... i have a square wave with frequency of 100hz.. & Triangle wave with 3sec time delay... Now I dont know how to superimpose these 2 waveforms (Like square)?? I googled more but i didn't get any details related this...

(These types of waveform are using for treatment purpose in physiotherapy feild )

Can any one please help me how to superimpose square wave in to triangle wave...

Thanks in advance...
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
47,928
Helped
14,143
Reputation
28,545
Reaction score
12,827
Trophy points
1,393
Location
Bochum, Germany
Activity points
278,099
Superimpose isn't the correct term in my opinion (also in the first case). The problem is about modulating one waveform with another, respectively multiplying the waveforms. An analog multiplier can perfectly achieve this.

As a special case, multiplying with a square wave can also be achieved by an analog switch (as you did in the first case). On/off switching a triangular wave with a 100 Hz waveform would be a simple solution for the second problem and can avoid a multiplier, I think.
 

Kral

Advanced Member level 4
Joined
Mar 28, 2005
Messages
1,326
Helped
280
Reputation
558
Reaction score
85
Trophy points
1,328
Location
USA
Activity points
13,418
It wold be helpful if you could show a sketch depicting what the waveform should look like.
 

Senthilkumar_rjpm

Full Member level 2
Joined
Jul 21, 2009
Messages
123
Helped
15
Reputation
30
Reaction score
15
Trophy points
1,298
Location
chennai
Activity points
2,039
Thank you FvM....
I accept Superimpose may not be a correct technical term... thats some local language (here in my company) to identify this concept thats all...
How i switch (On/Off) triangular wave FvM... Is there any circuit?? can u pls give me more details or Links regarding this?

---------- Post added at 11:11 ---------- Previous post was at 11:06 ----------

It wold be helpful if you could show a sketch depicting what the waveform should look like.
Thanks Mr.Kral....
Actually i provdivde details sketch in my question tag... (i dind't understand what sketch i show here) If you tell any particular sketch i must show it here...
 

umesh49

Full Member level 4
Joined
May 29, 2006
Messages
218
Helped
25
Reputation
50
Reaction score
21
Trophy points
1,298
Location
Detroit USA
Activity points
2,633
Well, you need a multiplier circuit to do this. You can use any SPDT (Say 1P1G3157QDBVRQ1) and connect square wave to S and B1 with triangle to B2. You should be getting desired output.

Umesh.
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
47,928
Helped
14,143
Reputation
28,545
Reaction score
12,827
Trophy points
1,393
Location
Bochum, Germany
Activity points
278,099
How i switch (On/Off) triangular wave FvM... Is there any circuit??
I was referring to your existing circuit and thought, the connection would be obvious:
Connect the triangle to pin 1 and the 100 Hz square wave to pin 10.
 

Senthilkumar_rjpm

Full Member level 2
Joined
Jul 21, 2009
Messages
123
Helped
15
Reputation
30
Reaction score
15
Trophy points
1,298
Location
chennai
Activity points
2,039
I was referring to your existing circuit and thought, the connection would be obvious:
Connect the triangle to pin 1 and the 100 Hz square wave to pin 10.
Thank you FvM sir... But as per this logic we ll get triangle wave with 100hz interruption.. That means there is a gap for 100hz inbetween triangle wave... But here i need 100hz wave form (not gap) inside of triangle wave for my purpose... because, Furtherly i want to amplify this combination of wave forms... Anyhow you are triggering me to think some another angle I will think & come back to you... Mean time you also please tell me some more ideas... Thank you onece again...

---------- Post added at 16:11 ---------- Previous post was at 16:07 ----------

Well, you need a multiplier circuit to do this. You can use any SPDT (Say 1P1G3157QDBVRQ1) and connect square wave to S and B1 with triangle to B2. You should be getting desired output.

Umesh.
Thanks mr umesh... That ic you suggested me is not available in our local market (chennai). & if i purchase some other cities or import means too much of cost.. pls refer me some another ic (DIP package is most welcome) if you know...
 

perumal.seenivasan

Newbie level 3
Joined
Aug 20, 2010
Messages
4
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Location
Chennai, India
Activity points
1,302
Hi Senthil,

According to me, what FvM suggested "Connect the triangle to pin 1 and the 100 Hz square wave to pin 10" should work for you.

The waveform that you want to achieve is not clearly mentioned. It can lead to 2 final waveforms. But both can be achieved by inserting/not inserting a NOT logic in the square wave path.
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
47,928
Helped
14,143
Reputation
28,545
Reaction score
12,827
Trophy points
1,393
Location
Bochum, Germany
Activity points
278,099
In fact, the 4052 is just acting as an analog switch. But you should draw the intended waveform exactly.
 

biff44

Advanced Member level 5
Joined
Dec 24, 2004
Messages
4,852
Helped
1,354
Reputation
2,704
Reaction score
1,035
Trophy points
1,393
Location
New England, USA
Activity points
36,625
If you want a ramping 100 hz square wave, you will need an analog multiplier, not a digital circuit. Try the analog devices AD633, and input the ramp to x1 and the 100 hz signal to y1.

You will have to generate the ramp somewhere. You can have a somewhat non-linear ramp by just R-C filtering a 1 bit signal. If that is not linear enough for you, you can charge/discharge a capacitor with current sources made of transistors.
 

umesh49

Full Member level 4
Joined
May 29, 2006
Messages
218
Helped
25
Reputation
50
Reaction score
21
Trophy points
1,298
Location
Detroit USA
Activity points
2,633
If you are searchnig in market, yuo can ask for a analog multiplxer or SPDT. You can order a sample from TI, they are really fast to deliver you the free sample.
 

Senthilkumar_rjpm

Full Member level 2
Joined
Jul 21, 2009
Messages
123
Helped
15
Reputation
30
Reaction score
15
Trophy points
1,298
Location
chennai
Activity points
2,039
In fact, the 4052 is just acting as an analog switch. But you should draw the intended waveform exactly.
Yes sir... i agree that 4052 acting as an analog switch.. the wave form i drawn in my first post is exact sir...



---------- Post added at 14:04 ---------- Previous post was at 14:03 ----------

If you are searchnig in market, yuo can ask for a analog multiplxer or SPDT. You can order a sample from TI, they are really fast to deliver you the free sample.
Thank you umesh.. let me try...
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
47,928
Helped
14,143
Reputation
28,545
Reaction score
12,827
Trophy points
1,393
Location
Bochum, Germany
Activity points
278,099
If you are searchnig in market, yuo can ask for a analog multiplxer or SPDT.
^
You did realize, that the original post #1 is already using an analog multiplexer?
If you want a ramping 100 hz square wave, you will need an analog multiplier, not a digital circuit.
If the square wave can be treated as a binary signal (0/1 or -1/+1), an analog switch will be sufficient as a multiplier, as already stated by several contributers.

the wave form i drawn in my first post is exact
If so, it won't bring up these doubts...

P.S.: Do you intend this kind of waveform? It can be easily generated with an analog switch.

 
Last edited:

Senthilkumar_rjpm

Full Member level 2
Joined
Jul 21, 2009
Messages
123
Helped
15
Reputation
30
Reaction score
15
Trophy points
1,298
Location
chennai
Activity points
2,039
^

P.S.: Do you intend this kind of waveform? It can be easily generated with an analog switch.

Yes Mr.FvM... i need this wave foem exactly... Is it comes in this (Your) Logic (Connect the triangle to pin 1 and the 100 Hz square wave to pin 10.)?
 

biff44

Advanced Member level 5
Joined
Dec 24, 2004
Messages
4,852
Helped
1,354
Reputation
2,704
Reaction score
1,035
Trophy points
1,393
Location
New England, USA
Activity points
36,625
Sorry, did not realize the 4052 was an analog multiplexer--thought it was a digital gate.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top