In what application is gallium arsenide used as a semiconductor material in preference to germanium or silicon?
- In high-current rectifier circuits
- In high-power audio circuits
- In microwave circuits
- In very low frequency RF circuits
Which of the following semiconductor materials contains excess free electrons?
- Insulated gate
Why does a PN-junction diode not conduct current when reverse biased?
- Only P-type semiconductor material can conduct current
- Only N-type semiconductor material can conduct current
- Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
- Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator
What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?
- Insulator impurity
- N-type impurity
- Acceptor impurity
- Donor impurity
What is the alpha of a bipolar junction transistor?
- The change of collector current with respect to base current
- The change of base current with respect to collector current
- The change of collector current with respect to emitter current
- The change of collector current with respect to gate current
What is the beta of a bipolar junction transistor?
- The frequency at which the current gain is reduced to 1
- The change in collector current with respect to base current
- The breakdown voltage of the base to collector junction
- The switching speed of the transistor
Which of the following indicates that a silicon NPN junction transistor is biased on?
- Base-to-emitter resistance of approximately 6 to 7 ohms
- Base-to-emitter resistance of approximately 0.6 to 0.7 ohms
- Base-to-emitter voltage of approximately 6 to 7 volts
- Base-to-emitter voltage of approximately 0.6 to 0.7 volts
What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?
- Corner frequency
- Alpha rejection frequency
- Beta cutoff frequency
- Alpha cutoff frequency
What is a depletion-mode FET?
- An FET that exhibits a current flow between source and drain when no gate voltage is applied
- An FET that has no current flow between source and drain when no gate voltage is applied
- Any FET without a channel
- Any FET for which holes are the majority carriers
In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?
In Figure E6-2, what is the schematic symbol for a P-channel junction FET?
Why do many MOSFET devices have internally connected Zener diodes on the gates?
- To provide a voltage reference for the correct amount of reverse-bias gate voltage
- To protect the substrate from excessive voltages
- To keep the gate voltage within specifications and prevent the device from overheating
- To reduce the chance of the gate insulation being punctured by static discharges or excessive voltages
What do the initials CMOS stand for?
- Common Mode Oscillating System
- Complementary Mica-Oxide Silicon
- Complementary Metal-Oxide Semiconductor
- Common Mode Organic Silicon
How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?
- They are both low impedance
- An FET has low input impedance; a bipolar transistor has high input impedance
- An FET has high input impedance; a bipolar transistor has low input impedance
- They are both high impedance
Which semiconductor material contains excess holes in the outer shell of electrons?
What are the majority charge carriers in N-type semiconductor material?
- Free electrons
- Free protons
- Free neutrons
What are the names of the three terminals of a field-effect transistor?
- Gate 1, gate 2, drain
- Emitter, base, collector
- Emitter, base 1, base 2
- Gate, drain, source