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    Urgent!!!

    hi..can anybody tell me how to convert a sine wave form into a square waveform by using op-amps(IC-741 specifically)....its my term project and i have just half a week left to submit it so plzzz hurry and reply..plz be elaborative and include diagrams if possible..thanks.regards

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    Re: Urgent!!!

    Dude, no one in this forum will do someone else's work. We only HELP. It is your work so you have to do it yourself.

    However I will help you.

    In order to convert a sine wave into a square wave you only have no use an Opamp (like IC-741) using a non-inverting amplifier circuit with a very large gain.

    The very large gain willl make the circuit saturate quickly, transforming your sine into a square.

    This site has exactly what you need:
    http://www.wisc-online.com/Objects/V...spx?ID=SSE7906

    You should use the "non-inverting amplifier", and not the "inverting" for 2 reasons:

    1) It does not invert the sinal (I supose that's what you want)

    2) It has very high input impedance (which is always good)



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    Re: Urgent!!!

    hmmm..yeah that'l do it..thanks..ur a life saver!..:D



    •   Alt13th May 2010, 19:24

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    Urgent!!!

    Or just use the opamp like a comparator - no feedback.

    Keith
    I started life with nothing and I've still got most of it left. (Seasick Steve)



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    Re: How to convert sine wave into square wave using op-amp

    Or just use the opamp like a comparator - no feedback.
    Yeah, that's right. Don't know how I didn't remebered that, how silly of me



    •   Alt14th May 2010, 16:20

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    Re: How to convert sine wave into square wave using op-amp

    ohk thank you for your feedback . i was actually able to "test run" my circuit in the lab..but you see there's now a tiny miny BIG problem..i am now suppose to convert my square wave output into a trangular wave.:(..Now how i do that?..and also to convert a sine wave into square wave using IC-741 op-amp?...and my project is now worth 50% weightage of my total course..what a misery!!



    •   Alt16th May 2010, 22:03

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    How to convert sine wave into square wave using op-amp

    You need an integrator.

    Keith
    I started life with nothing and I've still got most of it left. (Seasick Steve)



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    Re: How to convert sine wave into square wave using op-amp

    Keith is right, you need an integrator. Check this out:

    http://www.wisc-online.com/objects/V...spx?ID=SSE5303



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    Re: How to convert sine wave into square wave using op-amp

    that was an excellent help sir!!...i really appreciate it..and the slide show well that was so elaborative and easy to understand:)..thanks once again.you ppl are great help..kkep up the good work:D



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    Re: How to convert sine wave into square wave using op-amp

    hey!! hey.!!:D..i made the project and m just a day away from showing it to my teacher..guys ive made the integrator and adjusted the but i didnt have any idea what i was doing actualy..i read it somewhere that if you change the resistance and capacitance you can adjust the wave into traingular wave but what i want to ask is that is there any specific easy to understand "formula" for voltage output of an integrator?..not that one that includes an 'integral' type of stuff but a simple universal formula so i can easily understand it and make my teacher understand it as well:)..thanks waiting for ur feedback



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    How to convert sine wave into square wave using op-amp

    Unfortunately an integrator integrates, so it is difficult to avoid integration in the explanation:

    http://en.wikipedia.org/wiki/Operati...ing_integrator

    In simple terms, the output will decrease (because it is inverting) at a rate determined by the resistor and capacitor at dV/dT=-Vin/RC so if you had 100k and 100nF and a 5V signal, for example, the output would change at the rate of 500V/s.

    Keith.

    Added after 3 minutes:

    The simple explanation, by the way, is that the opamp keeps the inverting input at zero volts, so the current in the resistor is Vin/R. This current must go through the capacitor and the equation for a capacitor charge (Q=CV), when differentiated gives I=C.dV/dt. So, dV/dt=I/C = Vin/RC. The minus sign appears because of the dire4ction of the current in the capacitor, resulting in -Vin/RC.

    Keith.
    I started life with nothing and I've still got most of it left. (Seasick Steve)



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    Re: How to convert sine wave into square wave using op-amp

    Perhaps TANSAH wants to see an integral explicitely in the formula.
    Therefore, read this explanation for an intergator circuit (without signal inversion):
    * Voltage across a capacitor: Vc=(1/C)∫idt with i=Vin/R (due to virtual ground at the inverting opamp terminal)
    * Thus, Vc=(1/RC)∫(Vin)dt.
    * For Vin=const. this leads to Vc=(1/RC)*Vin*t (>>linear ramp prop. to time t).

    Perhaps this helps.



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    Re: How to convert sine wave into square wave using op-amp

    yeah i think i have understood most of it..thanks once again ppl:)



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