Question

Which of the following voltages may be considered as a safe and sufficient voltage for the operation of a LED?

(a) 0.7 V

(b) 5 V

(c) 2.7 V

(d) -5 V

I have been asked this question in a job interview.

My question is based upon Types of Diode and their Testing topic in section Diode Circuit of Analog Circuits

Answer 1

The correct choice is (c) 2.7 V

Best explanation: The safe and sufficient operating voltage range for LED is between 1.7 V to 3.3 V. Hence, 2.7 V is the best option.