Analog vs Digital Signals

1. Definition

In electronics, signals are how information (like sound, light, or data) is represented and transferred.
There are two main types of signals: Analog and Digital.

  • Analog Signals: Continuous values (smooth waveforms).
  • Digital Signals: Discrete values (steps, usually 0s and 1s).

2. Analog Signals

  • Vary continuously over time.
  • Can take infinite values within a range.
  • Examples: sound from a microphone, light intensity, temperature.

Visual Example:
A smooth sine wave curve. PWM signal example

3. Digital Signals

  • Represented in discrete steps (0 or 1, HIGH or LOW).
  • More reliable for computers and microcontrollers.
  • Examples: ON/OFF switch, binary data, PWM control signals.

Visual Example:
A square wave (only HIGH and LOW levels).

PWM signal example

4. Key Differences

Feature Analog Digital
Values Continuous (infinite) Discrete (0/1)
Signal Shape Smooth (sine wave) Square (steps)
Example Temperature, sound, light Switches, microcontrollers
Noise Sensitivity More sensitive to noise Less sensitive

5. Applications

  • Analog: Music, sensors (temperature, light, sound).
  • Digital: Computers, microcontrollers (Arduino, Raspberry Pi).

6. Safety Note

Always check if your circuit needs analog input (A0 pin) or digital input/output (D0–Dx pins) on Arduino/boards, to avoid wiring mistakes.

7. Video Explanation

Video coming soon