AD/DA conversion

What sampling frequency is needed to sample an analog signal containing components up to 20 kHz without aliasing?

  1. A10 kHz or more
  2. BExactly 20 kHz
  3. CA frequency higher than 40 kHz
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Answer: C. A frequency higher than 40 kHz

By the sampling theorem, the original signal can be reconstructed if it is sampled at more than twice its highest frequency. Twice 20 kHz is 40 kHz. The 44.1 kHz sampling frequency of music CDs was chosen based on the upper limit of human hearing, about 20 kHz.

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More AD/DA conversion questions

  1. Which is a characteristic of a flash AD converter?
  2. Which correctly describes the operation of a successive-approximation (SAR) AD converter?
  3. What is the maximum quantization error of an ideal AD converter? (LSB: the voltage corresponding to one least significant bit)
  4. Which is a characteristic of a delta-sigma (ΔΣ) AD converter?
  5. For a 10-bit AD converter with a full-scale input of 1.024 V, what voltage corresponds to 1 LSB?