Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEETPhysicsSemiconductors

An oscilloscope monitoring a logic circuit shows that the output Y drops to a logic LOW ( 0 ) state if and only if both inputs A and B are simultaneously at a logic HIGH ( 1 ) state. At all other times, the output Y remains at a logic HIGH ( 1 ) state. Which of the following Boolean expressions correctly represents the relationship between the inputs and the output?

Options

  1. AY = A B
  2. BY = A B
  3. CY = A + B
  4. DY = A + B

Correct answer

C. Y = A + B

Step-by-step solution

From the given description, the output Y = 0 only when A = 1 and B = 1 . For all other combinations ( (0,0), (0,1), (1,0) ), the output Y = 1 . This behavior corresponds exactly to the truth table of a NAND gate. The Boolean expression for a NAND gate is Y = A B . According to De Morgan's theorem, the complement of a product is equal to the sum of the complements: A B = A + B Therefore, the correct Boolean expression is Y = A + B . Answer: Y = A + B

Practice Semiconductors on Quantrex Academy →

More from Semiconductors

For two inputs A and B and output Y, the Boolean expression for NOR gate is 2026For an n-type semiconductor, the relation between the number density ' n_h ' and ' n_e ' is 2026A silicon crystal is doped with 5 10¹⁷ cm ⁻³ atoms of boron. The electron concentration (n_e) at room temperature is (n_i = 1.5 10¹⁰ cm ⁻³) 2026If the current gain in common-base configuration ( ) of a transistor increases from 0.95 to 0.96, the percentage change in current gain in common-emitter configuration ( ) is appro 2026Out of the following what is used to detect the intensity of light ? 2026The color of light emitted by an LED is determined primarily by which of the following factors? 2026Which of the following is true for a p-type semiconductor? 2026In case of semiconductors, the band gap between the valence band and conduction band is 2026 Full Semiconductors list All NEET PYQs