JEE Mains · Physics · STD 12 - 14. Semicondutor electronics
The maximum rated power of the LED is \(2\) mW and it is used in the circuit with input voltage of \(5\) V as shown in the figure below. The current through resistance \(R_S\) is \(0.5\) mA. The minimum value of the resistance of \(R_S\), to ensure that the LED is not damaged is _______ k\(\Omega\).
- A \(6\)
- B \(2\)
- C \(4\)
- D \(5\)
Answer & Solution
Correct Answer
(B) \(2\)
Step-by-step Solution
Detailed explanation
Since the reverse-biased diode branch acts as an open circuit, the entire current through the series resistor \(R_S\) flows through the LED: \(I_{\text{LED}} = I_{R_S} = 0.5\text{ mA}\) At the boundary condition where the LED dissipates its maximum rated power of…
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