PYQSide ExamsMy practice

Semiconductor Electronics · Question 13

JEE Main 2026 (Online) 28th January Evening ShiftMCQMedium📈 Topic in 58% papers+4−1
1

Two p-n junction diodes D1 and D2 are connected as shown in figure. A and B are input signals and C is the output. The given circuit will function as a . [figure]

  1. AND Gate
  2. OR Gate
  3. NOR Gate
  4. NAND Gate

Answer

(1) AND Gate

Solution

The p-sides of both diodes are joined to +5 V through R and their n-sides go to the inputs A and B.

If an input is 0 (low), the diode connected to it is forward biased and conducts; the output C is pulled down to 0.

Only when A = 1 and B = 1 (both at 5 V), neither diode conducts, no current flows through R and C = 5 V, i.e. C = 1.

Truth table: (A, B) = (0, 0) C = 0; (0, 1) C = 0; (1, 0) C = 0; (1, 1) C = 1

C = A B, the circuit works as an AND gate.

Answer: (1)

JEE Main 2026 (Online) 28th January Evening Shift

Keep practising — Semiconductor Electronics

2

A voltage regulating circuit consisting of Zener diode, having breakdown voltage of 10 V and maximum power dissipation of 0.4 W, is operated at 15 V. The approximate value of protective resistance in this circuit is .

JEE Main 2026 (Online) 24th January Morning Shift
3

Identify the correct truth table of the given logic circuit. [figure]

  1. arrayccc A & B & Y \ 0 & 0 & 0 \ 0 & 1 & 0 \ 1 & 0 & 1 \ 1 & 1 & 0 array
  2. arrayccc A & B & Y \ 0 & 0 & 0 \ 0 & 1 & 1 \ 1 & 0 & 1 \ 1 & 1 & 0 array
  3. arrayccc A & B & Y \ 0 & 0 & 1 \ 0 & 1 & 1 \ 1 & 0 & 1 \ 1 & 1 & 0 array
  4. arrayccc A & B & Y \ 0 & 0 & 1 \ 0 & 1 & 0 \ 1 & 0 & 1 \ 1 & 1 & 0 array
JEE Main 2026 (Online) 24th January Evening Shift
4

The following diagram shows a Zener diode as a voltage regulator. The Zener diode is rated at Vz = 5 V and the desired current in load is 5 mA. The unregulated voltage source can supply up to 25 V. Considering the Zener diode can withstand four times the load current, the value of resistor Rs (shown in circuit) should be . [figure]

  1. 100
  2. 10
  3. 1000
  4. 4000
JEE Main 2026 (Online) 23rd January Morning Shift
5

For the given logic gate circuit, which of the following is the correct truth table? [figure]

  1. arrayccc n & m & z \ 0 & 0 & 1 \ 0 & 1 & 1 \ 1 & 1 & 0 \ 1 & 0 & 0 array
  2. arrayccc n & m & z \ 0 & 0 & 1 \ 0 & 1 & 0 \ 1 & 1 & 1 \ 1 & 0 & 0 array
  3. arrayccc n & m & z \ 0 & 0 & 0 \ 0 & 1 & 1 \ 1 & 1 & 0 \ 1 & 0 & 1 array
  4. arrayccc n & m & z \ 0 & 0 & 1 \ 0 & 1 & 0 \ 1 & 1 & 0 \ 1 & 0 & 0 array
JEE Main 2026 (Online) 23rd January Evening Shift
6

Find the correct combination of A, B, C and D inputs which can cause the LED to glow. [figure]

  1. 1000
  2. 0011
  3. 0100
  4. 1101
JEE Main 2026 (Online) 22nd January Morning Shift
7

The correct truth table for the given input data of the following logic gate is : [figure]

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
JEE Main 2026 (Online) 22nd January Evening Shift
8

The given circuit works as : [figure]

  1. NOR gate
  2. OR gate
  3. AND gate
  4. NAND gate
JEE Main 2026 (Online) 21st January Morning Shift
9

The charge stored by the capacitor C in the given circuit in the steady state is . [figure]

  1. 7.5
  2. 5
  3. 10
  4. 12.5
JEE Main 2026 (Online) 21st January Evening Shift
10

The output voltage in the following circuit is (Consider ideal diode case) [figure]

  1. 0 V
  2. +5 V
  3. −5 V
  4. 10 V
JEE Main 2025 (Online) 8th April Evening Shift
11

In the following circuit, the reading of the ammeter will be (Take Zener breakdown voltage = 4 V) [figure]

  1. 60 mA
  2. 80 mA
  3. 10 mA
  4. 24 mA
JEE Main 2025 (Online) 7th April Morning Shift

All Semiconductor Electronics PYQs →

PDFDownload Semiconductor Electronics PYQs as PDF Free, with answer key and a QR code to every solution — print it or study offline⬇
All JEE Main Physics chapters
Class 11Units and MeasurementsMotion in a Straight LineMotion in a PlaneLaws of MotionWork, Energy and PowerSystem of Particles and Rotational MotionGravitationMechanical Properties of SolidsMechanical Properties of FluidsThermal Properties of MatterThermodynamics (Physics)Kinetic TheoryOscillationsWaves
Class 12Electric Charges and FieldsElectrostatic Potential and CapacitanceCurrent ElectricityMoving Charges and MagnetismMagnetism and MatterElectromagnetic InductionAlternating CurrentElectromagnetic WavesRay Optics and Optical InstrumentsWave OpticsDual Nature of Radiation and MatterAtomsNucleiSemiconductor ElectronicsExperimental Skills (Physics)