# IMPATT and BARITT Diodes MCQ’s

This set of RF & Microwave Circuit Design Multiple Choice Questions & Answers (MCQs) focuses on “IMPATT and BARITT Diodes”.

1. When a reverse bias voltage exceeding the breakdown voltage is applied to an IMPATT diode, it results in:
a) avalanche multiplication
b) break down of depletion region
c) high reverse saturation current
d) none of the mentioned

2. To prevent an IMPATT diode from burning, a constant bias source is used to maintain _______ at safe limit.
a) average current
b) average voltage
c) average bias voltage
d) average resistance

3. The material used to fabricate IMPATT diodes is GaAs since they have the highest efficiency in all aspects.
a) true
b) false

4. The number of semiconductor layers in IMPATT diode is:
a) two
b) three
c) four
d) none of the mentioned

5. If the length of the intrinsic region in IMPATT diode is 2 µm and the carrier drift velocity are 107 cm/s, then the drift time of the carrier is:
a) 10-11 seconds
b) 2×10-11 seconds
c) 2.5×10-11 seconds
d) none of the mentioned

6. IMPATT diodes employ impact ionization technique which is a noisy mechanism of generating charge carriers.
a) true
b) false

7. The resonant frequency of an IMPATT diode is given by:
a) Vd/2l
b) Vd/l
c) Vd/2πl
d) Vdd/4πl

8. If the length of the intrinsic region in IMPATT diode is 2 µm and the carrier drift velocity are 107 cm/s, then the nominal frequency of the diode is:
a) 12 GHz
b) 25 GHz
c) 30 GHz
d) 24 GHz

9. An essential requirement for the BARITT diode is that the intermediate drift region be completely filled to cause the punch through to occur.
a) true
b) false

10. If the critical field in a Gunn diode oscillator is 3.2 KV/cm and effective length is 20 microns, then the critical voltage is:
a) 3.2 V
b) 6.4 V
c) 2.4 V
d) 6.5 V

11. If the RMS peak current in an IMPATT diode is 700 mA and if DC input power is 6 watt, with the load resistance being equal to 2.5 Ω, the efficiency of the diode is:
a) 10.1 %
b) 10.21 %
c) 12 %
d) 15.2 %