Experiment 10: Monitoring Analog-Digital Conversion Signals

Objective: Observe and verify the behavior of Analog-to-Digital Conversion (ADC) signals, and understand how an analog signal is represented digitally by a microcontroller or sensor.

Steps:

  1. Connect the Signal Source to the ADC Input:
    • Identify the analog signal source, such as a potentiometer, sensor, or waveform generator.
    • Connect the signal source to the ADC input pin on the microcontroller or sensor device.
    • Ensure the analog signal is within the input range of the ADC (e.g., 0 to 3.3V or 0 to 5V, depending on the system).
    • If necessary, use an oscilloscope to verify the quality and amplitude of the analog signal.
  2. Capture the ADC Output Using the Logic Analyzer:
    • Connect the logic analyzer probe to the digital output pin of the microcontroller or sensor that provides the ADC conversion result.
    • Set the logic analyzer to capture the digital output at the appropriate sample rate, ensuring you capture the signal accurately over time.
    • Trigger the capture to start once the ADC begins converting the input analog signal to digital format (this could be based on a clock, interrupt, or manual triggering depending on the system).
  3. Analyze the Digital Representation of the Analog Signal:
    • Observe the captured digital signal, which will be a series of binary values corresponding to the ADC readings at specific time intervals.
    • Use the logic analyzer’s decoder to translate the digital signal into its numerical value (often in hexadecimal or decimal form).
    • Compare the digital values to the expected analog values based on the input signal to verify the accuracy of the ADC conversion.
    • If applicable, adjust settings such as sample rate, resolution, or reference voltage to optimize the ADC conversion and ensure proper scaling.

Expected Outcome:

By the end of this experiment, you will understand how an analog signal is converted into a digital representation by an ADC. You will also gain hands-on experience in monitoring and analyzing ADC signals using a logic analyzer to ensure proper conversion and signal integrity.