What is one characteristic of a linear electronic voltage regulator?

  1. It has a ramp voltage as its output
  2. It eliminates the need for a pass transistor
  3. The control element duty cycle is proportional to the line or load conditions
  4. The conduction of a control element is varied to maintain a constant output voltage


What is one characteristic of a switching electronic voltage regulator?

  1. The resistance of a control element is varied in direct proportion to the line voltage or load current
  2. It is generally less efficient than a linear regulator
  3. The controlled device's duty cycle is changed to produce a constant average output voltage
  4. It gives a ramp voltage at its output


What device is typically used as a stable reference voltage in a linear voltage regulator?

  1. A Zener diode
  2. A tunnel diode
  3. An SCR
  4. A varactor diode


Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

  1. A series current source
  2. A series regulator
  3. A shunt regulator
  4. A shunt current source


Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

  1. A constant current source
  2. A series regulator
  3. A shunt current source
  4. A shunt regulator


What is the purpose of Q1 in the circuit shown in Figure E7-3?

  1. It provides negative feedback to improve regulation
  2. It provides a constant load for the voltage source
  3. It increases the current-handling capability of the regulator
  4. It provides D1 with current
Circuit Diagram


What is the purpose of C2 in the circuit shown in Figure E7-3?

  1. It bypasses hum around D1
  2. It is a brute force filter for the output
  3. To self-resonate at the hum frequency
  4. To provide fixed DC bias for Q1
Circuit Diagram


What type of circuit is shown in Figure E7-3?

  1. Switching voltage regulator
  2. Grounded emitter amplifier
  3. Linear voltage regulator
  4. Emitter follower
Circuit Diagram


What is the main reason to use a charge controller with a solar power system?

  1. Prevention of battery undercharge
  2. Control of electrolyte levels during battery discharge
  3. Prevention of battery damage due to overcharge
  4. Matching of day and night charge rates


What is the primary reason that a high-frequency switching type high voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

  1. The inverter design does not require any output filtering
  2. It uses a diode bridge rectifier for increased output
  3. The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
  4. It uses a large power factor compensation capacitor to create free power from the unused portion of the AC cycle


What circuit element is controlled by a series analog voltage regulator to maintain a constant output voltage?

  1. Reference voltage
  2. Switching inductance
  3. Error amplifier
  4. Pass transistor


What is the drop-out voltage of an analog voltage regulator?

  1. Minimum input voltage for rated power dissipation
  2. Maximum amount that the output voltage drops when the input voltage is varied over its specified range
  3. Minimum input-to-output voltage required to maintain regulation
  4. Maximum amount that the output voltage may decrease at rated load


What is the equation for calculating power dissipation by a series connected linear voltage regulator?

  1. Input voltage multiplied by input current
  2. Input voltage divided by output current
  3. Voltage difference from input to output multiplied by output current
  4. Output voltage multiplied by output current


What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

  1. To cut down on waste heat generated by the power supply
  2. To balance the low-voltage filament windings
  3. To improve output voltage regulation
  4. To boost the amount of output current


What is the purpose of a "step-start" circuit in a high voltage power supply?

  1. To provide a dual-voltage output for reduced power applications
  2. To compensate for variations of the incoming line voltage
  3. To allow for remote control of the power supply
  4. To allow the filter capacitors to charge gradually


When several electrolytic filter capacitors are connected in series to increase the operating voltage of a power supply filter circuit, why should resistors be connected across each capacitor?

  1. To equalize, as much as possible, the voltage drop across each capacitor
  2. To provide a safety bleeder to discharge the capacitors when the supply is off
  3. To provide a minimum load current to reduce voltage excursions at light loads
  4. All of these choices are correct