30 Questions
What is the primary advantage of using voltage control devices in digital control systems?
They require very low control current
What is the relationship between iD and VDS in many VGS conditions?
It is the I-V characteristics
What is the region where the drain current differs by the gate-to-source voltage, and not by the drain-to-source voltage?
Saturation region
What is the state of the power MOSFET when the gate-to-source voltage is lower than the VGS(th)?
Cut-off
What type of device is a power MOSFET?
Unipolar, majority carrier
What is the term for the minimum voltage required to turn on a MOSFET?
VGS(th)
What is a key problem in using bipolar transistors as switches?
Providing sufficient base drive current
What is the purpose of the resistor in the example light-switch circuit?
To provide enough base current to ensure the transistor is saturated
What is the typical operation of a transistor in digital circuits?
As a switch, with only 'on' and 'off' values
What is the purpose of varying IB in the experiment described in the procedure?
To measure the effect of base current on the transistor's operation
What is the mode of the oscilloscope set to in the procedure?
X-Y mode
What is the voltage division ratio set on Channel 1 of the oscilloscope in the procedure?
5V/Div
What is the condition for an N-type conducting channel to be induced in a MOSFET?
Gate voltage is positive and beyond a threshold value
What is the purpose of the integral body diode in a MOSFET?
To carry full current in the reverse direction
What is the relationship between the conduction resistance (RDS(ON)) and the drain-source voltage (VDS) of a high voltage MOSFET?
RDS(ON) α VDS^2.5
What is the advantage of the positive temperature coefficient of RDS(ON) in MOSFETs?
It makes parallel operation of MOSFETs easy
What is the purpose of the trench gate technology in modern MOSFETs?
To lower the conduction resistance of the device
How are large MOSFETs typically fabricated?
By connecting multiple devices in parallel
What is the intrinsic standoff ratio (η) of a UJT?
The ratio of the variable resistance to the total resistance
What happens when the input voltage is greater than the drop across the diode plus the drop at the variable resistance R B1?
The device turns on and holes move from emitter to base
What is the region of operation characterized by a sudden increase in charge concentration in base1 region?
Negative resistance region
How many operating regions does a UJT have?
3
What is the purpose of setting the oscilloscope to X-Y mode in the procedure?
To display the UJT characteristics
What is the value of VBB set in the procedure?
5 V
What can trigger a thyristor into conduction when the anode is positive?
A short positive gate current pulse
What is the minimum current required to maintain the conduction state of a thyristor?
Holding current
What happens to the forward breakover voltage as the gate current increases?
It decreases
What is the characteristic of a thyristor with a high gate current?
It behaves like a diode with the entire forward blocking region removed
What is the characteristic of a modern thyristor?
High voltage and high current ratings
What is the effect of a rise in junction temperature on a thyristor?
It turns on the device
Understand the importance of providing sufficient base drive current when using bipolar transistors as switches. Learn how the transistor's current gain affects the ratio of collector and base currents. Analyze the role of the resistor in providing enough base current in a light-switch circuit.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
