Special-Purpose Diodes

A zener diode can be used as a 

• constant current source

  
  

• voltage reference

• both of the above

  
  

• none of the above

  
  

The zener current for the circuit shown is 

• 3.0 mA

• 6.0 mA

  
  

• 7.5 mA

  
  

• 9.0 mA

  
  

The load current for the circuit shown is

• 3.0 mA

  
  

• 6.0 mA

  
  

• 7.5 mA

  
  

• 9.0 mA

  
  

 If each of the zener diodes have a zener voltage of 5.0 V, the positive output will be limited to 

• +4.3 V

  
  

•  +5.0 V

  
  

• +5.7 V

  
  

• +10 V

  
  

A varactor is a diode used as a voltage-controlled

• current source

• light sensor

  
  

• resistor

  
  

• capacitor

  
  

The peak wavelength of an LED is related to

• the viewing angle

  
  

• the maximum power dissipated

  
  

• the color

  
  

• all of the above

  
  

The forward voltage drop for an LED depends on

• the type of diode

  
  

• the forward current

  
  

• the color

  
  

• all of the above

  
  

You would expect to find a laser diode in a

• automobile tail light

  
  

• bright sign board

  
  

• bar-code reader

  
  

• all of the above

  
  

A diode with a negative resistance region in its characteristic curve is a

• tunnel diode

  
  

• Schottly diode

  
  

• varactor

  
  

• photodiode

  
  

A photodiode

• has three layers

  
  

• operates with reverse bias

• is a light emitter

  
  

• all of the above