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  1. #1
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    PIC18F452 intead of VCO, is it possible?

    Hello Masters.

    I am back to school after 16 years, I want to finish the school and I have a project to do that.

    After 16 years, I am returning to study again all the concepts, I would like to know if it's possible to do the following with the PIC18F452:

    -The front end is any sensor, with some electronics components I have voltage from 0-5V.

    -PIC18F452 receives 0-5V with the ADC input.
    -with PIC18F452 I will have a sinusoidal signal and the amplitude depends of the input (0-5V), the sinusoidal signal should be an audible frequency.
    ************************
    Another project will receive the digital signal and with another electronic components will convert to analog signal and will be manage with a PC
    ************************

    I'm posting this... because I need your professional comments. If it's possible I would like to know, how can I generate a sinusoidal signal, of course the amplitude should be from -1 to 1.

    Thanks in advance.

    •   Alt3rd August 2014, 04:07

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  2. #2
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    Re: PIC18F452 intead of VCO, is it possible?

    Quote Originally Posted by ppperez View Post
    Hello Masters.


    I'm posting this... because I need your professional comments. If it's possible I would like to know, how can I generate a sinusoidal signal, of course the amplitude should be from -1 to 1.

    Thanks in advance.
    if you are dealing with a low frequency, e.g. less than 5KHz, a digital potentiometer such as Microchip;s MCP4011 is suitable
    http://www.microchip.com/wwwproducts...roduct=MCP4011

    you have a table of potentiometer values which at regular intervals (usinga timer interrupt) to send to the digital pot

    a similar techniqure sending values to a DAC (DtoA converter)

    for high accuracy and high (and very low) frequencies a DDS (Direct digital synthesizer) device may be used , e.g.
    http://www.analog.com/en/rfif-compon...s/product.html

    the advantage being you just send the DDS device the details of the frequency and phase you require and it does all the hard work!

    you may need external analogue circuits to get the voltage range and offset you require



    •   Alt3rd August 2014, 05:53

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  3. #3
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    Re: PIC18F452 intead of VCO, is it possible?

    Hello horace1.

    First of all... thanks for your comments.

    I would like to know if with that I can play audio. I already talked to my instructor and he told me that the goal is that PIC can play audio with the input of 0-5V with 0V not audio.

    As I told you, I'm returning to the school after a lot of time, I know that I have to study a lot of topics.

    Any comments, they are appreciate.

    Thanks in advance.



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