Learning objective
Analogue/digital conversion: Describe the principles of operation of: • an analogue to digital converter (ADC) • a digital to analogue converter (DAC). Know that ADCs are used with analogue sensors. Know that the most common use for a DAC is to convert a digital audio signal to an analogue signal.
Read the explanation, check the common trap, then practise with flashcards and questions.
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Topic
Representing images, sound and other data
Subtopic
Analogue/digital conversion
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Quick explanation
Analogue/digital conversion: Describe the principles of operation of: • an analogue to digital converter (ADC) • a digital to analogue converter (DAC). Know that ADCs are used with analogue sensors. Know that the most common use for a DAC is to convert a digital audio signal to an analogue signal
- This point belongs to Representing images, sound and other data, especially Analogue/digital conversion.
- You need to be able to analogue/digital conversion: Describe the principles of operation of: • an analogue to digital converter (ADC) • a digital to analogue converter (DAC). Know that ADCs are used with analogue sensors. Know that the most common use for a DAC is to convert a digital audio signal to an analogue signal.
- Use the linked flashcards and practice questions to check recall, then practise applying the idea in an exam-style answer.
Why it matters
This objective helps connect Analogue/digital conversion to exam-style questions, flashcards, and revision notes for Representing images, sound and other data.
Quick student answer
What is the primary purpose of an analogue-to-digital converter (ADC)?
Direct answer
To convert an analogue signal into a digital representation
Key terms
- Analogue-to-digital converter (ADC): A device that converts a continuously varying analogue signal, such as the output from an analogue sensor, into a digital representation.
- Digital-to-analogue converter (DAC): A device that converts a digital signal into a corresponding analogue signal, commonly for digital audio output.
Common trap
Reversing ADC and DAC: Remember: ADC means analogue to digital, while DAC means digital to analogue. Link ADCs with analogue sensors and DACs with digital audio output.
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