At temperatures above absolute zero, the probability or finding an electron at the fermi energy level is: 0 1 1/2 -1/2 For a thermal noise limited system, increasing the load resistance will____the signal to noise ratio. decrease not change increase Need more information For a shot noise limited system, decreasing the load resistance will____the signal to noise ratio. decrease not change increase Need more information The photocurrent in a reverse biased photodiode is____the irradiance. directly proportional to directly proportional to the square of inversely proportional to inversely proportional to the square of For an ideal photodiode, increasing the reverse voltage____the diffusion current. decreases will not change increases Need more information The best signal to noise ratio for a system is achieved when the system is_____noise limited. flicker thermal Nyquist shot In a forward biased pn junction, the predominant capacitance is the____capacitance. drift junction diffusion reverse For the same optical power and quantum efficiency, increasing the frequency of light striking a photodiode will___the photocurrent. decrease not change increase Need more information The energy of a photon can be increased by increasing its____or decreasing its____ wavelength, frequency amplitude, frequency frequency, wavelength phase angle, wavelength For a real diode, the____current increases with____reverse bias. diffusion, decreasing diffusion, increasing drift, decreasing drift, increasing A phototransistor has_noise than a photodiode. less more the same Need more information If an APD is replaced with a photodiode, the system wili approach a_noise limited system. flicker thermal quantum shot Diffusion of holes occurs from____to____. p to n Low to high concentrations n to p None of the above Electron drift current occurs from___to___. p to n high to low concentrations n to p None of the above As the temperature of a doped semiconductor is increased, the semiconductor becomes more: ntype intrinsic ptype Fermi limited.
36. (a) because they are frozen out and energy required to enter fermi band is not obtained.
37. (a) as the recieved power is LOW due to decrease in load resistance this decreases SNR
38. (c) as there will not be any change in load instances i.e the mean deviation
39. (a) photo diodes operate in reverse biased mode with respect to irradiance.
40. (b)
41. (d)
42. (c)
43. (b)
44. (c)
45. (c) diffusion current is due to opposite charge concentration during reverse bias
46. (c) the main reason why photodiodes are quite significantly behind major applications
47. (b)
48. (c) as it does\'nt obey ohms law
49. (a) General charge movement from p to n
50. (a) as temperature increases electrron jump into conduction band making them approximately characterized to n type semiconductors
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