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AC to DC

  1. Feb 9, 2014 #1

    I know what is AC signal and DC signals purpose.. but may I know how to convent AC signals to DC signals to feed in to the PIC??

    Help pls
  2. jcsd
  3. Feb 9, 2014 #2


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    2017 Award

    hi there

    tell us more about what you are trying to do....
    for example ( but not limited to) the source of the AC signal

  4. Feb 9, 2014 #3

    thanks for the reply..

    I am currently working on a autoguilded vechile project,
    i am doing the inductive sensor at the min...
    three parts to handle. sensor, motor and control system..

    help pls
  5. Feb 9, 2014 #4
    The overall project is like this

    A vehicle will follow a track which consists of a continuous loop of wire carrying a current of ~140mA (RMS) at a frequency of 10kHz
    The vehicle consists 3 parts, 2 Inductive sensors, motor driving and steering and control unit pic.

    The inductive sensor consists 2 parts, the sensor and rectifier
  6. Feb 9, 2014 #5


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    Gold Member

    with a PIC that has an ADC you can just amplify the coil outputs and then sample AC (dc offset of course) with the ADC.

    The amplifier should at least include a simple 10KHz filter unless you want to try an IIR in the PIC. (and an antialias filter)

    If the PIC is not fast enough for the above, you can follow the amp with a precision rectifier and then send DC to the PIC.

    So, amplifier with 10KHz filter, precision rectifier, ADC to the PIC.

    You can build 2 amp/filter/rectifier circuits or you can switch the input to 1 if your sample rate requirements are low enough. For example, 100 times a second would give you 10ms for the circuit to settle. (1000 cycles of 10Khz).
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