Electronic Devices-Thyristors

Electronic Devices-Thyristors
1. The ________ can be externally programmed to turn on at a desired anode-to-gate voltage level.
  • UJT
  • PUT
  • SCR
  • SCS
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2. You need a very efficient thyristor to control the speed of an AC fan motor. A good device to use would be
  • a 4-layer diode.
  • a PUT.
  • a triac.
  • a BJT.
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3. An application of a(n) ________ is in a lighting system for power interruptions.
  • SCR
  • SCS
  • diac
  • triac
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4. The silicon-controlled switch (SCS) is similar in construction to the
  • triac.
  • diac.
  • SCR.
  • 4-layer diode.
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5. The ________ can conduct current in either direction and is turned on when a breakover voltage is exceeded.
  • SCR
  • diac
  • SCS
  • triac
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6. You need to design a relaxation oscillator circuit. The most likely device to use might be
  • an SCR.
  • a UJT.
  • a triac.
  • a 4-layer diode.
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7. You have the schematic diagram of several types of circuits. Which of these circuits most likely uses a triac?
  • an oscillator
  • an ac motor control
  • a programmable oscillator
  • an amplifier
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8. The ________ is like a diac with a gate terminal.
  • triac
  • SCR
  • SCS
  • none of the above
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9. You have a need to use a device to trigger an SCR. A good one to use might be
  • an SCS.
  • a UJT.
  • a 4-layer diode.
  • a PUT.
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10. The SCR can be triggered on by a pulse at the
  • gate.
  • anode.
  • cathode.
  • none of the above
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