Electronic Devices-PNPN Question and Answer
Electronic Devices-PNPN Question and Answer
11. Which of the following devices has nearly the same turn-on time as turn-off time?
- SCR
- GTO
- SCS
- LASCR
12. Which of the transistors of an SCR are conducting when the SCR is fired and is in the conduction mode?
- npn
- pnp
- Both npn and pnp
- Neither npn nor pnp
13. For an SCS, a ________ pulse at the anode gate turns the device on, while a ________ pulse will turn it off.
- negative, positive
- positive, negative
15. Which of the following devices has (have) four layers of semiconductor materials?
- Silicon-controlled switch (SCS)
- Gate turn-off switch (GTO)
- Light-activated silicon-controlled rectifier (LASCR)
- All of the above
16. Which of the following parameters are usually provided by the manufacturer on the specification sheet for SCRs?
- Turn-on time (ton )
- Turn-off time (toff )
- Junction and case temperatures (tj and tc )
- All of the above
17. What is the maximum current (rms) rating for commercially available LASCRs today?
- 3 A
- 15 A
- 20 A
- 25 A
18. Which of the following areas is (are) applications of an SCS?
- Counters
- Pulse generators
- Voltage sensors
- All of the above
20. What is the typical value of the triggering anode gate for SCS devices?
- 1.5 mA
- 150 A
- 15 A
- 1 A