Question

What is the principle of digital oscilloscope?

Answer 1

A digital oscilloscope is an electronic instrument used to measure and display waveforms of electrical signals. It works by converting an analog electrical signal into a digital form, which allows for better analysis and visualization of the signal.

The basic principle of a digital oscilloscope is as follows:

1. Signal Acquisition:
   

   - The oscilloscope receives an analog electrical signal (e.g., from a circuit or device under test) via the input channels.
   - This signal is continuous, meaning it can vary smoothly over time.

1. Analog-to-Digital Conversion (ADC):
   

   - The analog signal is sampled at regular intervals by the oscilloscope's sampling system.
   - Each sample taken is converted into a digital value by the analog-to-digital converter (ADC).
   - The ADC represents the amplitude of the signal at each sample point as a digital number, which the oscilloscope can process and display.

1. Storage and Processing:
   

   - Once the signal is digitized, it is stored in the oscilloscope's memory. This allows the oscilloscope to display the waveform over time.
   - The processor inside the oscilloscope analyzes the digital signal, performs calculations, and controls the display based on user settings like time scale, voltage scale, and trigger settings.

1. Display:
   

   - The digital oscilloscope displays the waveform on a screen. The horizontal axis represents time, while the vertical axis represents the signal's voltage.
   - The waveform can be adjusted, zoomed in or out, or analyzed for various parameters such as frequency, peak value, and period.

1. Triggering:
   

   - To ensure stable and repetitive waveforms, the oscilloscope has a trigger system. This system allows the oscilloscope to start sampling at a specific point of the waveform to keep the display steady.
   - Without triggering, the waveform might appear as a jumbled mess on the screen.

Key Advantages:

1. High accuracy: Digital oscilloscopes provide precise measurements because digital signals can be processed, analyzed, and stored with high precision.
   

1. Complex analysis: Digital oscilloscopes can perform advanced calculations, such as frequency analysis, which analog oscilloscopes cannot easily do.
   

1. Storage: They can store waveforms for later analysis or comparison, which is not possible in traditional analog oscilloscopes.
   

In summary, a digital oscilloscope works by sampling an analog signal, converting it to a digital format, processing the data, and displaying the waveform on a screen for analysis.