Q1:

A GaAs LED is operating at 300k. Find the $\mathrm{\lambda }$of the radiated light in lm.(given E_g at 300k=1.4ev)

Q2:

Which of the following is an example of electroluminescent device?

Q3:

The wavelength beyond which photo-electric emission cannot takes place is called

Q4:

Optocoupler is a combination of

Q5:

The reverse current in the photodiode is due to?

Q6:

The Gun diode is made of

Q7:

Which type of doping does ESAKI diode has?

Q8:

The op-amp circuit shown is the figure is a filter the type of filter & its cut-off frequency one respectively.

Q9:

In the op-amp circuit shown, assume that the diode current follows the equation $I=I_S\text{ exp}\left(\frac{V}{V_T}\right).$for V_i = 2V, V₀ = V₀₁ and for V_i = 4 V, V₀ = V₀₂, the relationship b/w V₀₁ & V₀₂ is

Q10:

In the circuit shown, the op-amp has finite input impedance, infinite voltage gain and zero input offset voltages. The output voltages V_out is

Q11:

If the input to the ideal comparator shown in the figure is sinusoidal signal of 8v (peak to peak) without any DC component, then the o/p of the comparator has a duty cycle of.

Q12:

The op-Amp shown in fig. below is ideal. R =$\sqrt{\raisebox{1ex}{$L$}\!\left/ \!\raisebox{-1ex}{$C$}\right.}$ the phase angle between v₀ and v_i at w=$\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$\sqrt{LC}$}\right.$ is

R_f = 8, R₁= 2 and A = 45

Q13:

The circuit in the figure is a

Q14:

The first domain pole encountered in the frequency response of a compensated op -amp is approximately at.

Q15:

Which of the following are the non-linear applications of op-amp?

1. Current to voltage converter

2. Comparator

3. Peak detector

4. Limiter