Perhaps the best way to describe analog is to compare it to digital. A digital signal, simply put, will look like intermittent bursts of energy. The energy is either present or there is none. An analog signal, on the other hand, is a continuous wave that either rises or falls depending on the amount of input.

Analog is used in applications that need to measure a steady stream of inputs. For example, most speedometers in cars are analog. They constantly measure a vehicle’s change in speed, which is a continuous input as long as the vehicle is moving.

Read More about Analog

Many people may associate “analog” with outdated technology, such as analog TV sets that require long antennas to catch signals. But there are still analog devices that we use to this day. We will give a few examples below and some background information about analog.

What Are the Differences between Analog and Digital?

The analog definition is closely related to our understanding of digital signals. However, analog and digital signals vary in different ways. We’ll pinpoint some of their differences below.

analog vs digital
  • Data representation: Analog signals are continuous, varying signals that represent real-world phenomena, while digital signals are discrete, quantized signals that represent data in binary form.
  • Accuracy: Analog signals are generally more accurate than digital signals since they represent a broader range of values. In contrast, digital signals can only represent a limited range of values due to the fixed number of bits used to encode them.
  • Noise: Analog signals are more susceptible to noise and interference than digital signals, which can be accurately reconstructed even in the presence of noise.
  • Processing: Analog signals are processed using analog devices, while digital signals are processed using digital devices, such as computers and microcontrollers.
  • Storage: Analog signals are typically stored on analog media, such as cassette tapes and vinyl records, while digital signals are stored on digital media, such as CDs and hard drives.
  • Transmission: Analog signals are transmitted over analog channels, such as copper wire or radio waves, while digital signals are transmitted over digital channels, such as fiber optic cables and wireless networks.

How Does Converting Analog to Digital Work?

Analog-to-digital conversion (ADC) is the conversion of analog signals to digital ones for easier manipulation in digital communications. It is a three-part process that involves these steps:

How Does Converting Analog to Digital Work
  • Sampling: Samples of the analog signal are taken at fixed, regular intervals determined by the sampling rate. The higher the sampling rate, the more accurate the analog signal sample is, but this requires more processing power and storage.
  • Quantization: Each sample is then quantized or assigned a numerical value that depends on the number of bits used. An 8-bit ADC can have 256 possible values, while a 16-bit ADC can have 65,536 possible values.
  • Encoding: The quantized values are then encoded in binary form and transmitted using a series of 0s and 1s.

What Are Some Examples of Analog Signals?

Analog signals are continuously varying signals emitted in the physical world. Some examples include sound, temperature, light, pressure, and electric signals. These analog signals are present around us all the time. They can be processed, measured, and manipulated using analog devices.

What Are Some Examples of Analog Devices?

Analog devices can be electrical or non-electrical devices that measure, broadcast, and process analog signals. Analog computers and TV sets are some examples of electrical analog devices. 

On the other hand, examples of non-electrical analog devices include analog watches, clocks, pendulums, and acoustic rangefinders. While some of these examples may seem obsolete, analog devices are still commonly used today.

For example, most vehicles still use speedometers indicating the moving car’s speed through a needle connected to a magnetic field generated when the car moves. Another analog device we still use today are seismometers, which are devices that record an earthquake’s intensity.

How Do Analog Devices Work?

Analog devices use electronic components, such as transistors, capacitors, resistors, and inductors, to process and change the characteristics of analog signals. Here is a brief definition of each component.

  • Transistors: Devices that amplify or switch electronic signals and power.
  • Capacitors: Smoothen voltage fluctuations and filter out unwanted noise when processing analog signals by storing energy in an electric field.
  • Resistors: Limits the flow of electric current.
  • Inductors: Smoothen voltage fluctuations and filter out unwanted noise when processing analog signals by storing energy in a magnetic field.

The next time you see a car speedometer or an analog TV set, you know that these components are at work.

Key Takeaways 

  • Analog signals are continuous waves representing real-world phenomena like sound and temperature.
  • Digital signals are discrete, quantized signals represented in binary form.
  • Examples of analog devices include analog watches, car speedometers, and seismometers.
  • Analog devices use electronic components like transistors, capacitors, resistors, and inductors to process analog signals.
  • ADC involves sampling, quantizing, and encoding analog signals.
  • Analog signals are generally more accurate but more susceptible to noise than digital signals.
  • Analog and digital signals differ in representation, accuracy, noise, processing, storage, and transmission.
  • Despite the prevalence of digital technology, analog devices continue to play a role in various applications.

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