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Which of the following statements is wrong about noise in Operational Amplifiers?


16) Which of the following statements is wrong about noise in Operational Amplifiers?
  1. Thermal noise is the result of random motion of the charge carriers in a resistor. [Option ID = 2893]
  2. Shot noise arises from the discrete nature of the current flow in electronic devices. [Option ID = 2894]
  3. Popcorn noise is caused by imperfect semiconductor surface conditions. [Option ID = 2895]
  4. Flicker noise occurs in active devices at very high frequencies. [Option ID = 2896]

Answer: D

Solution
Statement 1 is True: Thermal noise is indeed the result of random motion in a resistor.
Statement 2 is True: Shot noise does arise from the discrete nature of current.
Statement 3 is True: Popcorn noise is caused by surface/lattice conditions.
Statement 4 is FALSE: Flicker noise occurs at low frequencies, not very high frequencies. As frequency increases, flicker noise eventually disappears below the thermal noise floor.
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