Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Electronic Devices question

2013 · Shift 0 · Q49
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Electronic Devices
  5. /2013 · Shift 0 · Q49

Electronic Devices question

2013 · Shift 0 · Q49

JEE MainPhysicsElectronic DevicesMCQ+4 / −1
The I{\rm I}I-VVV characteristic of an LEDLEDLED is
  1. A
    JEE Main 2013 (Offline) Physics - Semiconductor Question 191 English Option 1
  2. B
    JEE Main 2013 (Offline) Physics - Semiconductor Question 191 English Option 2
  3. C
    JEE Main 2013 (Offline) Physics - Semiconductor Question 191 English Option 3
  4. D
    JEE Main 2013 (Offline) Physics - Semiconductor Question 191 English Option 4
View written solutionFree

Correct answer: A

  1. An LED (Light Emitting Diode) is a p-n junction diode that emits light when it is forward biased.

  2. Therefore, its III-VVV characteristic is essentially like that of a diode:

    • In forward bias, current remains very small up to a threshold voltage, then increases rapidly.
    • In reverse bias, only a very small reverse current flows until breakdown.

  3. So the correct graph must show:

    • negligible current for small forward voltages,
    • a sharp rise in current after the cut-in voltage,
    • very small reverse current.

  4. Since the stored correct answer is A, this implies option A is the graph matching the usual diode/LED III-VVV characteristic.

  5. Hence, the III-VVV characteristic of an LED is the diode-like forward characteristic with a knee voltage.

Therefore, the correct option is A.

PreviousNext

More from Electronic Devices

  • A diode detector is used to detect an amplitude modulated wave of 60% modulation by using a condenser of capacity 250 picofarad in parallel with a load resistance 100 kilo ohm. Find the maximum modulated frequency which could be… Includes diagram2013 · MCQ
  • Truth table for system of four NAND gates as shown in figure is: Includes diagram2012 · MCQ
  • The combination of gates shown below yields Includes diagram2010 · MCQ
  • The logic circuit shown below has the input waveforms ′A′ and ′B′ as shown. Pick out the correct output waveform. Output is Includes diagram2009 · MCQ
  • A p-n junction (D) shown in the figure can act as a rectifier. An alternating current source (V) is connected in the circuit. The current (I) in the resistor (R) can be shown by : Includes diagram2009 · MCQ
  • In the circuit below, A and B represent two inputs and C represents the output. The circuit represents Includes diagram2008 · MCQ
  • If in a p-n junction diode, a square input signal of 10V is applied as shown Then the output signal across RL​ will be Includes diagram2007 · MCQ
  • Carbon, silicon and germanium have four valence electrons each. At room temperature which one of the following statements is most appropriate ?2007 · MCQ